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ReviewMUSH 4/19/2016 1
Silicic Magma Reservoirs in the Earth’s Crust 1
2
3
Olivier Bachmann, Institute of Geochemistry and Petrology, ETH Zurich, 80924
Switzerland5
Christian Huber, School of Earth and Atmospheric Sciences, Georgia Institute of6
Technology,GA30332,USA7
Outline (for reviewing purpose only) 8
1Abstract9
2Introduction10
3Howcanwestudymagmareservoirs11
3.1Samplingvolcanicandplutoniclithologies12
3.2Studyingactivevolcanoes,gasandgeophysicalmeasurements13
3.3Reproducingtheconditionsprevailinginmagmachambersinthe14
laboratory15
Experimentalpetrology:16
a) Phaseequilibriumexperiments17
b) Rheologicalexperiments18
Rheologicalstudies19
Tankexperimentsformagmachamberprocesses20
3.4Overviewofmagmareservoirdynamicsfromtheoreticalmodels21
4Modelofmagmareservoir:focusingonthe“Mush”22
4.1Presenceofcrystal-poorrhyolites,andzonedignimbrites23
4.2The“Monotonousintermediates”-remobilizedmushes24
4.3Theunzoned,crystal-poortointermediatedeposits25
4.4Chemicalfractionationinmushyreservoirs:thedevelopmentof26
compositionalgapsinvolcanicsequences27
4.5Plutondegassingandvolatilecycling28
ReviewMUSH 4/19/2016 2
4.6Thehigheruptabilityofrhyoliticmeltpockets29
4.7TheExcessSparadox30
4.8Calderacycles31
5.Timescalesassociatedwithmagmareservoirs32
6.Frontiersinourunderstandingofmagmachamberevolution33
7Outlook34
8Acknowledgement35
9References36
37
Totalof15figures.38
39
1 Abstract 40
Magma reservoirs play a key role in controlling numerous processes in planetary41
evolution, including igneous differentiation and degassing, crustal construction and42
volcanism.Fordecades,scientistshavetriedtounderstandwhathappensinthesereservoirs,43
usinganarrayoftechniquessuchasfieldmapping/petrology/geochemistry/geochronology44
onplutonicandvolcaniclithologies,geophysicalimagingofactivemagmaticprovinces,and45
numerical/experimentalmodeling.This reviewpaper tries to follow thismulti-disciplinary46
frameworkwhilediscussingpastandpresent ideas.Wespecifically focuson recent claims47
thatmagma columnswithin the earth’s crust aremostly kept at high crystallinity (“mush48
zones”), and that the dynamicswithin thosemush columns, albeitmodulated by external49
factors(e.g.,regionalstressfield,rheologyofthecrust,pre-existingtectonicstructure),play50
an important role in controlling how magmas evolve, degas, and ultimately erupt. More51
specifically,weconsiderhowthechemicalanddynamicalevolutionofmagmaindominantly52
mushy reservoirs provides a framework to understand (1) the origin of petrological53
gradientswithindepositsfromlargevolcaniceruptions(“ignimbrites”),(2)thelinkbetween54
volcanic and plutonic lithologies, (3) chemical fractionation of magmas within the upper55
layersofourplanet,includingcompositionalgapsnoticedacenturyagoinvolcanicseries(4)56
volatilemigrationandstoragewithinmushcolumnsand(5)theoccurrenceofpetrological57
cyclesassociatedwithcaldera-formingeventsinlong-livedmagmaticprovinces.Therecent58
ReviewMUSH 4/19/2016 3
advances inunderstanding the innerworkingsof silicicmagmatismarepaving theway to59
exciting future discoveries, which, we argue, will come from interdisciplinary studies60
involving more quantitative approaches to study the crust-reservoir thermo-mechanical61
couplingaswellasthekineticsthatgoverntheseopensystems.62
63
2 Introduction 64
Determiningtheshape,size,depth,andstateofmagmasbodiesintheEarth’scrustas65
well as how they evolve over time remain key issues for a number of Earth Science66
communities.With a better determination of these variables, petrologists could construct67
more accurate chemical models of differentiation processes; magma dynamicists could68
postulatecausesformagmamigration,storage,andinteractionatdifferentlevelswithinthe69
crust; volcanologists could better predict the style and volume of upcoming volcanic70
eruptions; and geochronologists could construct an evolutionary trend with greater71
precision.Althoughourknowledgeonmagmaticsystemshasexpandedgreatlyoverthepast72
decades,muchremains tobedone toconstrain themulti-phase,multi-scaleprocesses that73
areatplayinthosereservoirsandtheratesatwhichtheyoccur.74
75
Previousattemptstosummarizethestateofknowledgeinthisfield(e.g.,Smith1979;76
Lipman 1984; Sparks et al. 1984; Marsh 1989a; de Silva 1991) have greatly helped77
crystallizingideasonthecontemporaneousstateofknowledgeandpossiblealleysforfuture78
directions to explore. Since then,manymorepublicationshaveattempted todrawmagma79
reservoirs geometries and internal complexities (see Figure 1 for a potpourri of such80
schematicdiagramsforseveralexamplesoflargecalderasystemsintheUSA,aswellasthe81
morerecentreviewsbyPetfordetal.2000;Bachmannetal.2007b;Lipman2007;Cashman82
ReviewMUSH 4/19/2016 4
andSparks2013;CashmanandGiordano2014;deSilvaandGregg2014).Atthisstage,itis83
clear that magmas are complex mixtures of multiple phases (silicate melt, H2O-CO2-84
dominatedfluid,andupto10differentmineralphasesinsomesystems)withverydifferent85
physical properties. For example, viscosity contrast betweenwater vapor and crystals can86
spanmorethan20ordersofmagnitude,andevenvarysignificantlywithinonegivenphase87
(e.g.,severalordersofmagnitudeforsilicatemelt),ascomposition-P-T-fH2O-fO2vary(Mader88
et al. 2013). Theway thesemagmasmove and stall in the crustwill therefore reflect the89
complexinteractionbetweenallthesephasesandthetypicallycolderwallrocks.90
91
Over the last decades, an impressive body of work has accumulated on the92
characterizationofmagmamainly through (1) high-precision, high-resolution geochemical93
work (with ever more powerful instruments, including the atom-probe, e.g., Valley et al.94
2014 and nanoSIMS in the recent past; e.g., Eiler et al. 2011; Till et al. 2015) and (2)95
experimental petrology (e.g., phase diagrams, trace element partitioning between phases,96
isotopic fingerprinting), culminating in powerful codes for thermodynamic modeling97
(GhiorsoandSack1995a;Boudreau1999;Connolly2009;Gualdaetal.2012).Thisworkwill98
continue to greatly improve the constraints thatwe place on thesemagmatic systems for99
years to come, but we argue that the field will have to take into account kinetic,100
disequilibrium processes, which are commonplace, and can be severe in the world of101
magmas.102
103
Thermodynamics andkinetics areboth valuable tounderstandmagmaticprocesses104
andkineticsisboundtobecomeevenmoreimportantinthefollowingdecadesaswestrive105
ReviewMUSH 4/19/2016 5
tobetter constrain the timescaleofdynamicalprocessesassociatedwithmagma transport106
andevolutioninthecrust.ThisCentennialVolumeofAmericanMineralogistappearsasan107
appropriate landmark to summarize the recent advances on the subject, and bring the108
multiplefacetsofthisproblemtogethertobetterframethefuturedirectionsofresearch.109
110
Figure1:Recent schematicdiagrams for the threebigactive caldera systems in theWestern111
USA.Therearemanyothercalderasystemsaroundtheworld(e.g.,HughesandMahood2008),112
andthefocusonexamplesfromtheUSAhereissolelyduetopersonalacquaintance.(a)Valles113
caldera;Wilcock et al. 2010, (b) LongValley caldera,Hildreth 2004, (c) Yellowstone,Official114
websiteandLowensternandHurvitz2008.115
The most exciting scientific challenges are, we believe, those that are driven by116
enigmas arising by observations ofNature. Below are a few examples of key questions or117
long-standingobservationsthatrelatetomagmareservoirsandmagmaticdifferentiation:118
119
ReviewMUSH 4/19/2016 6
1. Thefundamentaldichotomyinsupervolcanicdeposits(alsocalledignimbritesorash-120
flow tuffs), which show, in most cases, (A) compositionally and thermally zoned121
dominantlycrystal-poorunits(sometimesgradingtocrystal-richfaciesattheendof122
the eruption, Lipman 1967; Hildreth 1979; Wolff and Storey 1984; Worner and123
Schmincke1984;deSilva andWolff1995)and (B) strikinglyhomogeneous crystal-124
rich dominantly dacitic units (the “Monotonous Intermediates” of Hildreth 1981),125
known tobesomeof themostviscous fluidsonEarth (WhitneyandStormer1985;126
Francis et al. 1989; de Silva et al. 1994; Scaillet et al. 1998b; Lindsay et al. 2001;127
Bachmannetal.2002;Bachmannetal.2007b;Huberetal.2009;Folkesetal.2011b;128
seealsoBachmannandBergantz2008b;Huberetal.2012aforreviews).129
2. The striking resemblance in chemical composition (for major and trace elements)130
between the interstitial melt in crystal-rich silicic arc magmas and the melt-rich131
rhyoliticmagmas(BaconandDruitt1988b;HildrethandFierstein2000;Bachmannet132
al.2005).133
3. Theubiquitousobservationofmagmarecharges fromdepthprior toeruptions,and134
their putative role on the remobilization of resident (often crystal-rich) magmas135
(“rejuvenation”),forlargeandsmalleruptions(e.g.,Sparksetal.1977;Pallisteretal.136
1992;Murphyetal.2000;Bachmannetal.2002;BachmannandBergantz2003;Wark137
etal.2007;Molloyetal.2008;Bachmann2010a;CooperandKent2014;Klemettiand138
Clynne2014;WolffandRamos2014;Wolffetal.2015).139
4. The long-noticed compositional gap in volcanic series, coined the Bunsen-Daly Gap140
afterR.BunsenandR.Daly’searlyobservations(Bunsen1851;Daly1925;Daly1933),141
and confirmed in many areas worldwide since (Chayes 1963; Thompson 1972;142
ReviewMUSH 4/19/2016 7
Brophy1991;Thompsonetal.2001;Deeringetal.2011a;Szymanowskietal.2015)143
evenwherecrystalfractionation,whichshouldleadtoacontinuousmeltcomposition144
atthesurface,dominates(Bonnefoietal.1995;Geistetal.1995;Peccerilloetal.2003;145
Macdonaldetal.2008;DufekandBachmann2010;Sliwinskietal.2015).146
5. The complex relationship between silicic plutonic and volcanic units with possible147
hypotheses (not mutually exclusive in plutonic complexes) ranging from plutons148
being“failederuptions”(crystallizedmelts;Tappaetal.2011;Barbonietal.;Glazner149
et al. 2015; Keller et al. 2015) to plutons being “crystal graveyards” (crystal150
cumulates; Bachl et al. 2001; Deering and Bachmann 2010; Gelman et al. 2014;151
Putirka et al. 2014; Lee and Morton 2015). Related to this volcanic-plutonic152
connection is the corollary that granites sensu stricto (evolved, high-SiO2, low Sr153
composition)appeartobelesscommonthantheirvolcaniccounterparts(e.g.,Navdat154
database,Hallidayetal.1991;Hildreth2007;Gelmanetal.2014).155
6. Theobservationthatsilicicplutons,whenfullycrystallized,containlittlevolatileleft156
(typically less than 1wt%H2O that is bound up in theminerals; e.g., Caricchi and157
Blundy2015)despitethefacttheystartedwithvolatileconcentrationsabove6wt%,158
implyingsignificantlossofvolatileatdifferentstagesofthemagmabodies’evolution159
(e.g., by first and second boiling, pre-, syn-, and post-eruption degassing, see for160
example Anderson 1974; Wallace et al. 1995; Candela 1997; Lowenstern 2003;161
Webster2004;Wallace2005;Bachmannetal.2010;Blundyetal.2010;Sillitoe2010;162
BakerandAlletti2012;HeinrichandCandela2012).163
7. Thewell-known“ExcessS”,highlightedbythemuchhigherScontentreleasedduring164
eruptions(measuredbyremotesensingorestimatedfromicecorerecords)thatcan165
ReviewMUSH 4/19/2016 8
beaccountedforbythemeltinclusiondata(i.e.petrologicestimate,see,forexample,166
reviewsbyWallace2001;Costaetal.2003;Shinohara2008).167
8. The remarkable cyclic activity observed large-scale volcanic systems, which168
culminates in caldera-forming eruptions (“caldera cycles”) that can repeat itself169
severaltimes,e.g.,themulti-cycliccalderasystemssuchasYellowstone(Hildrethetal.170
1991;BindemanandValley2001;Christiansen2001;LowensternandHurvitz2008),171
Southern RockyMountain Volcanic field (e.g., Lipman 1984; Lipman 2007; Lipman172
and Bachmann 2015), Taupo Volcanic Zone (e,g,,Wilson 1993;Wilson et al. 1995;173
Suttonetal.2000;Deeringetal.2011a;Barkeretal.2014),HighAndes(e.g.Pitcheret174
al. 1985;Petfordet al. 1996;Lindsayet al. 2001; Schmitt et al. 2003;deSilvaet al.175
2006;KlemettiandGrunder2008),CampiFlegreii(e.g.Orsietal.1996;Civettaetal.176
1997;Gebaueretal.2014)andAegeanarc(e.g.Bachmannetal.2012;Degruyteretal.177
2015).178
179
Allthosequestions/observationsrequireanoverarchingconceptofmagmachamber180
growth and evolution that ties together these seemingly disparate concepts. Before181
attemptingsuchatask,thesectionbelowbrieflyoutlinesthemethodsthataretypicallyused182
toinferthestateofthesereservoirs,highlightingsomeoftheirstrengthsandlimitations.183
184
3 How can we study magma reservoirs? 185
3.1 Sampling volcanic and plutonic lithologies 186
The foundation of volcanology is motivated by observations of ongoing and past187
volcanic activity,with the purpose of understanding the underlying processes that govern188
ReviewMUSH 4/19/2016 9
the evolutionofmagmatic systemsonEarth andotherbodies of the solar system (Wilson189
andHead1994).However, large-scaleeruptionsarerare(Simkin1993;Masonetal.2004)190
and as volcanologists/petrologists we rely much on a forensic approach: studymagmatic191
rocks (bothplutonicandvolcanic) that formed/erupted in thepast, and try to reconstruct192
the conditions (P, T, fO2, fH2O, fSO2, …) that prevailed in the reservoirs at the time of193
formationoreruption(see, forexample,areviewoftechniquesbyPutirka2008orBlundy194
and Cashman 2008). Of course, volcanic and plutonic lithologies do not provide the same195
type of information, and could/should be complementary. Volcanic rocks carry limited196
spatialcontextforthereservoir,butprovideaninstantaneoussnapshotintothestateofthe197
magmabody justbefore theeruption. Incontrast,plutonicrockspresenta time-integrated198
image of themagma accumulation zone, oftenwith a history spanningmulti-million years199
(e.g.,Greeneetal.2006;Walkeretal.2007;Schoeneetal.2012;Cointetal.2013),forwhich200
wecanteaseoutsome informationaboutsizesandshapesofmagmasbodies.Muchof the201
geochemicaldataacquiredoverthelastcenturyisnowtabulatedinlargedatabasessuchas202
Georoc (http://georoc.mpch-mainz.gwdg.de/georoc/), EarthChem203
(http://www.earthchem.org),andNavdat(http://www.navdat.org),providingaremarkable204
resource toanalyzeglobalgeochemicalproblems(seerecentpapersofKellerandSchoene205
2012;Chiaradia2014;Gelmanetal.2014;Glazneretal.2015;Kelleretal.2015).206
207
3.2 Studying active volcanoes, gas and geophysical measurements 208
Measuring gases coming out of active volcanoes provides us with some key209
information about the state ofmagmatic systems (e.g., Giggenbach 1996; Goff et al. 1998;210
Edmondsetal.2003;Burtonetal.2007;Humphreysetal.2009).Due to their lowdensity211
ReviewMUSH 4/19/2016 10
andviscosity,volcanicgasescanescapetheirmagmatictrapsandprovide“atelegramfrom212
theEarth’sinterior”,aslaidoutbyoneofthepioneersofgasmeasurements,SadaoMatsuo213
(e.g.,Matsuo1962).Forexample, theabundanceofchemicalspecies likeHe,CO2,orClcan214
helpdeterminethetypeofmagmathatisdegassing(Shimizuetal.2005),andthepotential215
volumethatistrappedinthecrust(LowensternandHurvitz2008).Asmentionedabove,the216
amountofSreleasedduringeruptionsisalsokeyinestimatingthepresenceofanexsolved217
gasphaseinthemagmareservoirpriortoaneruption(Scailletetal.1998a;Wallace2001;218
Shinohara 2008). As discussed by Giggenbach (1996), the composition of volcanic gases219
measuredat thesurface integratesbothdeep, i.e.magmareservoir,processesandshallow220
processes within the structure of the edifice and possibly the interaction with a221
hydrothermalsystem.Assuchitisoftenchallengingtodirectlyrelategascompositiontothe222
conditions of shallow magma storage (e.g., Burgisser and Scaillet 2007) and a better223
monitoring strategy is generally to look for relative changes in gas compositions and224
temperatureratherthanfocusingonabsolutevalues.225
226
With the exception of gas measurements, imaging active magma reservoirs mainly227
involves geophysicalmethods. Several techniques arenowavailable, andprovidedifferent228
pictures of activemagmas bodies. Such techniques include (1) seismic tomography (both229
activeandpassivesources;seeforexampleDawsonetal.1990;Lees2007;WaiteandMoran230
2009; Zandomeneghi et al. 2009; Paulatto et al. 2010, ambient noise tomography, e.g.,231
Brenguieretal.2008;Fournieretal.2010;Jayetal.2012),(2)Magneto-Telluricsurveys(e.g.,232
Hill et al. 2009; Heise et al. 2010), (3) deformation studies using strain-meter, GPS, and233
satellitedata(e.g.,Massonnetetal.1995;Hooperetal.2004;Lagiosetal.2005;Newmanet234
ReviewMUSH 4/19/2016 11
al.2006;Hautmannetal.2014),(4)muontomographyonsteepvolcanicedifices(Tanakaet235
al.2007;Gibertetal.2010;Marteauetal.2012;Tanakaetal.2014).236
237
Geophysicalmethods arebasedon the inversionof signals transmitted through the238
crustandmeasuredfromorclosetothesurface.Thechoiceofmethodsand,inseveralcases,239
the frequencybandof thesignalsstudieddependson the targetedresolutionanddepthof240
interest. Geophysical methods probe variations in physical properties caused by the241
presenceofpartiallymoltenreservoirsinthecrustandprovide2or3dimensionalimagesof242
these systems. These inversions however do not provide an unequivocal picture of the243
thermodynamicalstateofthemagmastorageregion,becauseseveralvariables(meltfraction,244
temperature, exsolved gas content, composition, connectivity of the various phases) affect245
the elastic, magnetic and electric properties of magmas. Similarly, surface deformation246
signalsarenotonly functionof thestate,shape,orientationandsizeofamagmabody,but247
also depend on the crustal response to stresses around the body (through anelastic248
deformationandmovementalongweaknessplanessuchasfracturesandfaults;Newmanet249
al.2006;Greggetal.2013).250
251
Insummary,geophysicalsurveysmainlyprovideconstraintsaboutthedepth,shape252
andextentofapartiallymolten(orhot)regionunderanactivevolcanicedifice.Themany253
surveys using inSAR, GPS field campaigns or ambient noise tomographywhere, as for gas254
monitoring,thefocusliesonrelativechangesratherthantheeffectivestateofthereservoir,255
have significantly increased our ability to monitor volcanic unrest (see recent review by256
Acocella et al. 2015). They efficiently highlight rapid (decadal or less) changes in the257
ReviewMUSH 4/19/2016 12
mechanical state of magmatic systems, which is generally difficult to achieve using258
petrologicaldatasets.However,thespatialscalesprobedbygeophysicalimagingtechniques259
are limited by the resolution of the method considered. Under most circumstances, the260
spatial resolution remains greater or equivalent to the kilometer scale (Waite and Moran261
2009;Farrelletal.2014;Huangetal.2015),which is instarkcontrastwith theextremely262
highresolutionofgeochemicalandpetrologicaldata.Assuch,geophysicalinversionscanbe263
thought of as upscaling filters of the state of heterogeneous multiphase reservoirs. A264
fundamental assumption underlying these inversions is that spatial resolution is265
commensurable with a Representative Elementary Volume (REV) where the physical266
propertiesoftheheterogeneousmediumcanbe(linearly)averagedoutintoasingleeffective267
value(amoredetaileddiscussionofthelimitationsimposedbythisassumptionisprovided268
insection6).269
270
3.3 Reproducing the conditions prevailing in magma chambers in the laboratory 271
Experimentalpetrology:272
273
a) Phaseequilibriumexperiments274
275
Starting with N.L. Bowen at the turn of the 20th century, many geoscientists have276
applied experimental studies to study the thermodynamics that control the assemblage of277
phasesinmagmaswithdifferentbulkcompositions.Fornearlyacentury,alargeamountof278
data has been collected on crystal-melt stability and composition as a function of several279
variables(P,T,fugacitiesofvolatileelementsandoxygen,compositionsofmagmas,cooling280
ReviewMUSH 4/19/2016 13
rate,…).Muchofthisdataisnowavailableindatabases,someinweb-basedportals,asisthe281
case for thegeochemicaldata(see forexampleBerman1991;HollandandPowell2011or282
LEPR, http://lepr.ofm-research.org/YUI/access_user/login.php). The data sets range from283
crystal-melt equilibria in the mantle melting zones (e.g., see Poli and Schmidt 1995, and284
pMELTSdatabase,http://melts.ofm-research.org/Database/php/index.php)tolowercrustal285
(e.g.,MuntenerandUlmer2006;Alonso-Perezetal.2009)anduppercrustal conditions in286
manydifferentsettings(e.g.,JohnsonandRutherford1989;JohannesandHoltz1996;Scaillet287
and Evans 1999; Costa et al. 2004; Almeev et al. 2012; Gardner et al. 2014; Caricchi and288
Blundy2015).289
290
For shallow magma reservoirs in arcs, a third phase, volatile bubbles, is also291
commonly present. This exsolved volatile phase does not only affect the thermo-physical292
properties of magmas (see below) but can also impact greatly the partitioning of some293
volatiletraceelementsandthereforeinfluencethechemicalfractionationthattakesplacein294
magma reservoirs. Laboratory experiments have played a major role in determining the295
solubilityofvolatilephases(H2O,CO2,S,CL,F,…)asafunctionofpressure,temperatureand296
meltcomposition(seethereviewbyBakerandAlletti2012andreferencestherein).Several297
species, such as Cl and S compounds, have a strong influence on the fractionation and298
transportofpreciousmetalsoutofmagmareservoirs, to the siteoforedepositsandhave299
therefore receiveda thoroughattention (Scaillet et al. 1998a;Williams-Jones andHeinrich300
2005;Zajaczetal.2008;Sillitoe2010;Fiegeetal.2014).301
302
ReviewMUSH 4/19/2016 14
Chemicalequilibriumbetweenthemeltandnewlyformedcrystalsorcrystalrimsis303
oftenadecentassumption,but thisassumptionbreaks loosewhenchanges takingplace in304
the reservoir aremore rapid than the equilibration timescale (see Pichavant et al. 2007).305
Suchrapidchangesinreservoirs’conditionscaninclude:(1)magmarechargesandpartial306
307
308
309
310
311
(incomplete)mixing,(2)efficientphysicalseparationofmineraland/orbubble-melt,312
and (3) during rapid pressure drops associated with mass withdrawal events (eruptions,313
dikepropagationoutof the chamber). In theseparticular cases,kinetics controls themass314
balancebetweenthedifferentphases;onethereforeneedstoconsiderdiffusionofelements315
in silicate melts and minerals, as well as mineral and bubble growth or dissolution. The316
diffusive transportof chemical species in silicatemelts isa strong functionof (a)viscosity317
(whichisaproxyforthedegreeofpolymerizationofthemelt),(b)dissolvedwatercontent,318
and(c)toalesserextent,oxygenfugacity(redoxconditionsinthemagmaaffectspeciation).319
Webringtheattentionof the interestedreadersto thereviewofY.ZhangandD.Cherniak320
(ZhangandCherniak2010)foradditionalinformationonthistopic.321
322
Thepresenceofkineticsisreadilyobservedinmineralzoningpatternsbecausesolid-323
statediffusionisgenerallyordersofmagnitudeslowerthandiffusioninsilicatemelts.Over324
thelastdecade,severalmodelshavebeendevelopedtousethediffusionofcationsinsilicate325
ReviewMUSH 4/19/2016 15
minerals and retrieve timescales relevant to thedynamic evolutionofmagmasbefore and326
duringeruptions.Thesemodelsrestheavilyonexperimentswherethekineticsofdiffusion327
asfunctionoftemperatureandcompositionismeasured(SeereviewofZhangandCherniak328
2010 and reference therein). Diffusionmodeling inminerals informs us on the interval of329
timebetweenasignificantchangeinthermodynamicconditionsofthemagma(mixingfrom330
recharges for example) and the time atwhich theminerals transitions across the closure331
temperature (e.g., eruption) where subsequent diffusion can be ignored. To date, studies332
have explored the diffusion of a growing quantity of cations in hosts such as quartz,333
plagioclase,pyroxene,biotiteandolivines(formoremaficsystemsthantheonesconsidered334
here;SeeFigure2forpublishedexamples).335
336
ReviewMUSH 4/19/2016 16337
ReviewMUSH 4/19/2016 17
338
339
Figure2: Examples of diffusionalprofiles inquartz crystals fromTaupo,NZ (Matthews et al.340
2012), in pyroxene crystals from the Bishop Tuff, Ca, USA (Chamberlain et al. 2014a) and341
plagioclasecrystalsfromCosigüina,Nicaragua(Longpreetal.,2014).342
343
Stableisotopescanalsoprovideinformationregardingthethermodynamicconditions344
(equilibrium fractionationbetweendifferentphases) andkinetics (kinetic fractionation) in345
themagma.Becauseofimprovedaccuracyandspatialresolutionofanalyticalmeasurements,346
thereisagrowinginterestinusingdifferentstableisotopesystems,suchasO,S,Caaswellas347
othermajorelements,tofingerprinttheoxidationstateofmagmas(MetrichandMandeville348
2010; Fiege et al. 2015), crustal assimilation (e.g., Friedman et al. 1974; Taylor 1980;349
Hallidayetal.1984;Eileretal.2000;BindemanandValley2001;Boroughsetal.2012),or350
mixingprocessesbetweenmagmaswithdifferentcompositions(Richteretal.2003;Watkins351
etal.2009a).352
353
b) Rheologicalexperiments354
355
Themigration, convection anddeformationofmagmaticmixtures in the crusthave356
directimplicationsontherateandefficiencyoffractionationprocesses,onthecoolingrateof357
magmareservoirsanderuptiondynamics(e.g.,GonnermannandManga2007;Lavalléeetal.358
2007;Cordonnieretal.2012;GonnermannandManga2013;Parmigianietal.2014;Pistone359
ReviewMUSH 4/19/2016 18
et al. 2015). The response of magmas to differential stresses is complex, owing to the360
multiphase nature of these systems. Several research groups have performeddeformation361
experiments to better constrain rheological laws pertinent tomagmas (Spera et al. 1988;362
Lejeune andRichet 1995; Caricchi et al. 2007; Ishibashi and Sato 2007; Champallier et al.363
2008; Cimarelli et al. 2011;Mueller et al. 2011; Vona et al. 2011; Pistone et al. 2012;Del364
Gaudio et al. 2013; Laumonier et al. 2014;Moitra and Gonnermann 2015). These studies365
have focused on diverse aspects of the rich non-linear dynamics of the rheology of366
suspensions,suchas(1)theeffectofthecrystalvolumefraction,(2)theeffectiveshearrate,367
(3) the effect of polydisperse crystal size distributions and various crystal shapes. These368
results clearly show that suspensions become very stiff as crystal content approach or369
exceed40to50percentofthevolumeofthemagma,althoughtheyprovidelittleinformation370
about the onset and magnitude of a yield stress for crystal-rich suspensions. Even more371
challenging is the development of physically consistent rheology laws for three-phase372
magmas because of the additional complexity of the capillary stresses (coupling bubbles,373
melt, and crystals), bubble deformation, three phases lubrication effects and possible374
coalescence(Pistoneetal.2012;Trubyetal.2014).375
376
Magma rheology experiments have been synthesized to yield different empirical377
(Lavalléeetal.2007;Costaetal.2009)andsemi-empirical(Petford2009;Maderetal.2013;378
Faroughi and Huber 2015) models for the deformation of magmas under shear flow379
conditions.Themechanicalbehaviorofmagmasremainsarichfieldforfutureinvestigations,380
and several important challenges remain to constrain the rate at which magma flows in381
reservoirsanduptothesurface.Theyinclude:382
ReviewMUSH 4/19/2016 19
• How to treat multiphase rheology when phase separation takes place383
concurrently?384
• Howdobubblesinteractwithcrystalssuspendedinviscousmelts,howdoes385
thisbehaviordependonthestrainrateandvolumefractionsofeachphases?386
• Can we constrain the yield strength of crystal-rich magmas under magma387
chamberconditions(imposedstressesratherthanimposedstrain-rate)?388
• Byrheology,weoftenrestrictourselvestomeasuretheshearviscosityusing389
experimentsormodelsthatrelatestressanddeformationunderverysimple390
geometries.Asviscosity is a tensor, is itpossible tomeasure its anisotropy391
fornon-linearmultiphasesystemswithcomplexcrystalshapesundervarious392
strainratesandconditionspertinenttomagmachambers?393
394
The rheology of a magma body should therefore be considered as a dynamical395
quantity, which can vary significantly (orders ofmagnitude) because of changes in stress396
distributions, variations in crystal-melt-bubble phase fractions and potentiallymany other397
factors.398
399
Several other physical properties have a resounding impact on the evolution of400
magmasinthecrust.Magmasarefarfromthermalequilibriuminthemidtouppercrustand401
heattransferinandoutofthesebodiescontrolstheirchemicalanddynamicevolutiontoa402
greatextent(Bowen1928;McBirneyetal.1985;Nilsonetal.1985;McBirney1995;Reiners403
et al. 1995; Thompson et al. 2002; Spera and Bohrson 2004). In that context, the heat404
capacity,latentheat,andthermalconductivityofsilicatemelts/mineralsandCO2-H2Ofluids405
ReviewMUSH 4/19/2016 20
areimportanttoestablishthetimescaleoverwhichthesereservoirscrystallizeinthecrust406
and by extension the vigor of convective motion in these systems. It is important to407
emphasizethatthermalconvectionintheclassicalsenseisnotdirectlyapplicabletomagma408
chambersundermostconditions,becausedensitycontrastsbetweenthedifferentphasesfar409
exceeds those by thermal expansion (e.g.,Marsh andMaxey 1985; Bergantz andNi 1999;410
Dufek and Bachmann 2010). Additionally, the rate of crystallization directly impacts the411
coolingrateofmagmas(duetonon-linearreleaseof latentheatduringcrystallization,e.g.,412
Huberetal.2009;Morse2011), and this latentheatbuffering becomesdominantas silicic413
magmas approach eutectic behavior near their solidus (Gelman et al. 2013b; Caricchi and414
Blundy2015).Somerecentstudieshavetestedhowthetemperaturedependenceofthermal415
properties influence the cooling and crystallization timescales ofmagmas in the crust and416
showedthat theseeffectsaresometimesnon-trivial(Whittingtonetal.2009;Gelmanetal.417
2013b;deSilvaandGregg2014).418
419
Tankexperimentsformagmachamberprocesses:420
421
Anelegantapproachtostudythecomplexmultiphasefluiddynamicsthattakesplace422
inmagmareservoiristoresorttolaboratorytankexperiments(seeforexample,McBirneyet423
al.1985;Nilsonetal.1985;JaupartandBrandeis1986;MartinandNokes1988;Shibanoetal.424
2012).Experimentsprovidethemeanstoinvestigatesomeaspectsofthecomplexnon-linear425
dynamicsthatprevailinthesesystems,however,inmostcases,itisdifficultorimpossibleto426
satisfydynamical similitudewith realmagmatic systems.Nevertheless, experiments reveal427
interesting feedbacks that may have been overlooked and can serve as a qualitative428
ReviewMUSH 4/19/2016 21
assessmentofhowprocessescoupletoeachother.Oneofthemaindirectionsforlaboratory429
fluiddynamicsexperimentsistostudyhowmagmaticsuspensionsbehaveat lowReynolds430
number during convection, phase segregation and magma recharges with mixing (e.g.,431
McBirney 1980; Sparks et al. 1984; McBirney et al. 1985; Davaille and Jaupart 1993;432
Koyaguchi et al. 1993). Here, the term suspension is used loosely to describe as both433
suspensionwithsolidparticles(crystals)andbubblyemulsions.434
435
Asdiscussedthroughoutthisreview(andclearlyalludedtobyearlypetrologistssuch436
asR.Dalyasfarbackasthe1910s,e,g,Daly1914),magmabodiesareopenreservoirsthat437
exchangemassandenergywiththeirsurroundings.Chemicalheterogeneitiesandzonations438
thenreflecteitherphaseseparationbygravity(e.g.,McBirney1980;Hildreth1981;Sparkset439
al. 1984; McBirney 1993) or incomplete mixing between magmas with different440
compositions(Eichelberger1975;Dunganetal.1978;BlakeandIvey1986;Eichelbergeret441
al.2000).Becausebuoyancyforcesrelatedtocompositionaldifferences(includingpresence442
ofvariousphasesofvariabledensities)exceedthermalbuoyancyeffectbyseveralordersof443
magnitude,mechanicalconvectionandstirringaredominatedbychemicalvariations,bubble444
rise and/or crystal settling. Strong spatial contrasts in bulk viscosity because of mixing445
between magmas with different compositions, contrasts in crystal content or thermal446
gradientsalsotendtostabilizeagainsthybridizationormagmamixing(SparksandMarshall447
1986; Turner and Campbell 1986; Koyaguchi and Blake 1989; Davaille and Jaupart 1993;448
Jellinek and Kerr 1999). Mixing in magma reservoirs can also be accelerated during449
eruptions,wheresubstantialstressdifferentialscanbegeneratedbydecompressionorroof450
collapse(BlakeandCampbell1986;BlakeandIvey1986;Kennedyetal.2008).451
ReviewMUSH 4/19/2016 22
452
Figure3.Injectionofnegativelybuoyantdropletsof(lowviscosity)waterdyedingreenintoa453
tankfilledwith(moreviscous)siliconoil(fromFaroughiandHuber2015).Dropletinteractions,454
eveninthepresenceofdroplettrains,cansignificantlyreducethesettlingvelocityanddecrease455
therateofphaseseparation.456
Convection strongly influences phase separation, which in turns controls chemical457
differentiation. Several groups have investigated the effect of crystals (Jaupart et al. 1984;458
BrandeisandJaupart1986;BrandeisandMarsh1990;Koyaguchietal.1993;Shibanoetal.459
2012)bubbles(Huppertetal.1982;Thomasetal.1993;CardosoandWoods1999;Phillips460
andWoods2002;Namikietal.2003),andshapesofreservoirs(e.g.,deSilvaandWolff1995)461
onconvectivemotion.Thepresenceofcrystalsorbubblescontrolsthegravitationalenergy462
potentialthatisconvertedtokineticenergyduringconvection,asexperimentsconfirmthat463
ReviewMUSH 4/19/2016 23
they impact convection even at relatively small volume fractions. Obviously, suspended464
phases affect convection, but convection itself also influences crystal settling or bubble465
migration. For example,Martin andNokes 1988;Martin andNokes 1989 used a series of466
experimentstoquantifythetimescaleoverwhichaconvectingsuspensionofcrystalsclears467
outbecauseofStokessettling.Hydrodynamicinteractionsbetweenthedifferentphasescan468
significantly reduce the settling velocity and affect phase separation even at low particle469
(bubblesorcrystals)volumefractions(FaroughiandHuber2015,seeFig.2).470
471
3.4 Overview of magma reservoir dynamics from theoretical models 472
473
Numericalstudiesenableustoisolatespecificdynamicalfeedbacksandtoprovidea474
frameworktounderstandthecomplextemporalevolutionofthesesystems,whichcanoften475
be challenging to infer from natural samples or laboratory experiments where dynamic476
similarity is difficult to satisfy. Numerical approaches based on different sets of starting477
assumptionsandgoverningequationshavebeenusedtoaddressquestionssuchas:478
• The chemical evolution of open-system magma reservoirs undergoing479
assimilation,crystalfractionationandmagmaevacuation.480
• Thethermalevolutionandlongevityofmagmareservoirsinthecrust.481
• The relative importance of crustal melting vs. crystal fractionation of more482
maficparentsindrivingtheevolutionofmagmastowardssiliciccompositions.483
• The pressure variations in and around magma chambers and stability of484
reservoirsfollowingrecharges.485
• Gasexsolutionandhowitimpactsthedynamicsinshallowmagmareservoirs.486
ReviewMUSH 4/19/2016 24
487
a)Boxmodels(nospatialdimensions)488
The first category of studies summarized below is based on boxmodels where the489
reservoirsareconsideredhomogeneousandinternalstructuresarenotexplicitlyaccounted490
for. These models involve ordinary differential equations that depend solely on time (no491
spatialdependency)andbyextensionassumethathomogenizationtakeplaceoverashorter492
timescale than the processes considered. In other words, in these models, the different493
phases(melt,crystals,sometimesbubbles)areassumedtoremaininthermalandchemical494
equilibriumwitheachotheroverthescaleofthewholereservoir.495
496
Since the seminal work of H. Taylor and D. DePaolo (Taylor 1980; DePaolo 1981),497
where a box model was constructed to infer the relative importance of assimilation and498
crystalfractionationprocessesonthetraceelementsandisotopicrecord,manystudieshave499
expandedon themethod to relate chemical tracers to the actualdynamicalprocesses that500
control the evolution of magmatic systems. The scope of these models ranges from non-501
linear reactor models (Bonnefoi et al. 1995) investigating the development of bimodal502
compositionsfromasinglemagmaticsystemtoconstrainingtheeffectofmeltextractionon503
thechemicalsignatureoftheresidualcumulateandhigh-silicamelts(Gelmanetal.2014;Lee504
andMorton 2015) aswell as focusing on the development of crystal zonations in awell-505
mixed reservoir (Wallace and Bergantz 2002; Nishimura 2009). These models provide506
insights into thechemicalresponseofreservoirs tovarious fractionationprocesses,butdo507
notexplicitlytreatthesourceoftheseprocesses(e.g.,coolingandcrystallizationleadingto508
ReviewMUSH 4/19/2016 25
gravitational settling or the reheating of the surrounding crust and its partial509
melting/assimilation).510
511
As a first step towards answering these limitations, W. Bohrson and F. Spera512
developed,inaseriesofpapers(SperaandBohrson2001;SperaandBohrson2004;Bohrson513
and Spera 2007; Bohrson et al. 2014), a model that couples the mass balance of trace514
elements and isotopes in a reservoir where cooling and assimilation processes are515
parameterized. They also added a thermal energy equation for the reservoir. The energy516
balanceinopenmagmachambersisquitecomplexandinvolvesmorethanjustsensibleand517
latentheatcontributionsinresponsetotheheatlosstothesurroundingcrust.Evenwithin518
the assumption that the reservoir remains homogeneous and the phases remain in519
equilibriumatalltimes,enthalpyisconstantlytransferredfrommechanicalworktoheatand520
vice-versa.Asanexample, the injectionof freshmagma intoa reservoiraffects theenergy521
budget not only by providing a possible heat source but also exerts mechanical work522
(pressure changes) that affect the stability of the phases present in the magma. These523
feedbacks become even more important when shallow volatile-saturated systems are524
considered(HuppertandWoods2002;DegruyterandHuber2014;Degruyteretal.2015).It525
is therefore important to extend the energy conservation statement in these models to526
includemechanicalworkandphasechangeswhenpossible(henceintroducingaconsistent527
twowaycouplingbetweenthehotmagmareservoirandthesurroundingcrust;deSilvaand528
Gregg2014;DegruyterandHuber2014).529
530
b)Modelswithspatialdimensions531
ReviewMUSH 4/19/2016 26
532
Theassumptionofthermalandchemicalequilibriumatthescaleofthereservoirisuseful533
and allows us to draw interesting and informative conclusions on the general trends that534
govern magma chamber evolution. However, this assumption is untenable under most535
conditions.Introducingspatialheterogeneitiesinthemagmabodyandthereforeallowingfor536
somedegreeofdisequilibriumbetweenthephases(atleastdowntothescaleofthemodel’s537
resolution,wherelocalequilibriumisgenerallystillassumedbetweenphases)isnecessary538
to get realistic estimates of the temporal scales over which magma bodies evolve. More539
specifically, a spatiotemporaldescriptionofmagmareservoirsprovides theopportunity to540
testfortheconditionsunderwhichefficientmixingisnolongerpossible(Huberetal.,2009)541
and chemical differentiation by mechanical separation (flow) occurs. We will divide the542
spectrumofnumericalmodelsgearedtoaddressthesequestionsinto(1)thermalmodels543
ononehandand(2)coupledthermalandmechanicalmodelsontheotherhand.544
545
b.1Thermalmodels546
547
Thermalmodelsareconcernedonlywithoneaspectoftheenergybalanceandconsider548
only sensible and latent heat. These models involve various levels of complexity, from549
equilibrium crystallization, i.e. the amount of crystallization over each time step is that550
predicted from equilibrium thermodynamics (e.g. Annen et al. 2008; Leeman et al. 2008;551
Annen2009;Gelmanetal.2013b;KarakasandDufek2015)tothemodelofC.Michautand552
coworkerswherecrystallizationisconsideredkineticallylimited(MichautandJaupart2006).553
Equilibriumcrystallizationmodels relyonaconstitutiveequation that relates temperature554
ReviewMUSH 4/19/2016 27
and crystallinity for a given choice of magma composition and pressure, generally555
constrained experimentally or using thermodynamicmodels such asMELTS (Ghiorso and556
Sack1995b).Becausenomomentumconservationisconsidered,crystalsandmeltarestatic557
and bound to each other, i.e. no phase separation and by extension no chemical558
differentiation by crystal fractionation is possible. Heat is therefore transported only by559
diffusionwithinandoutofthemagmareservoir.Thesemodelshavebeenusedextensivelyto560
study the longevity of activemagma bodies in the crust as function of the rate ofmagma561
injections.Whiletheysuggesthighaverageratesofmagmainjectionstocounteracttheheat562
lost to thecrust, theyoverlook theroleofmechanicalprocessesandvolatileexsolutionon563
the energy balance in response to repeated magma recharges and sporadic evacuation564
events(Degruyteretal.2015).565
566
b.2Thermo-mechanicalmodels567
568
Another type of model accounts for the coupled momentum and enthalpy balance in569
magma reservoirs and has been used tomodel the thermal evolution aswell as chemical570
differentiation (by crystal fractionation and assimilation) in magmatic systems. In these571
models,themomentumbalanceiseitherparameterized(Huberetal.2009)orrequiresaset572
of coupled continuum equations that allows the different phases to separate from one573
another (Dufek and Bachmann 2010; Gutierrez and Parada 2010; Lohmar et al. 2012;574
SimakinandBindeman2012;Solanoetal.2012).Inthoselattermodels,thedifferentphases575
are coupled in the momentum equation through drag terms. The first numerical models576
appliedtomixingofchemicalheterogeneities(singlephasefluids)inmagmasbyconvective577
ReviewMUSH 4/19/2016 28
stirringwheredevelopedbyC.Oldenburgandcolleagues(Oldenburgetal.1989;Speraetal.578
1995), and highlighted the different rates of mixing by normal and shear strains. Later,579
Huberetal.,(2009)discussedamethodtocharacterizetheefficiencyofmixingbyconvective580
stirringintime-dependentsystemswherecoolingandcrystallizationdampentheefficiency581
of convection over time.Multiphasemixing by sinking crystal plumes initiated at thermal582
boundary layers has been studied extensively as the source of convection in magmas583
(BergantzandNi1999;DufekandBachmann2010;SimakinandBindeman2012).Thefocus584
of these models is to look at crystal fractionation (Bergantz and Ni 1999; Dufek and585
Bachmann2010;Solanoetal.2012)andcrustalassimilation(SimakinandBindeman2012)586
assourcesofchemicaldifferentiationformagmasemplacedinthecrust.587
588
At this stage, amodel that involves a thermo-mechanical solution to the crust-magma589
bodysystemsandthatalsosolvesfortheinternalfluidmechanicsandchemicalevolutionof590
thereservoir isyet tobecompleted (seeGreggetal.2013;DegruyterandHuber2014 for591
preliminary attempts to do this). Some of the processes associated with the mechanical592
response to thesereservoirs tomassadditionorwithdrawalcanoperateovermuch faster593
timescales than the thermal and chemical evolution of the reservoir and coupling these594
variousprocessesprovestobechallenging.595
596
The mechanical and chemical interaction between the many phases that coexist in597
magma reservoirs is complex. It is generally parameterized with simple constitutive598
empirical relationships (e.g. drag terms, interphase heat transfer coefficients). Because599
modelsareonlyasgoodastheassumptionstheyrelyon,itisimportanttorevisitthevalidity600
ReviewMUSH 4/19/2016 29
of these constitutivemodels that introduce the dynamical coupling between the different601
phasesincontinuummodels.Intruth,theseinteractiontermsinvolvelengthscalesthatare602
farbeyondtheresolutionofcontinuummodelsanditistheinterplaybetweencrystals,melt603
andpossiblygasbubblesthatdrivemostofthedynamicsinmagmabodies.Oneexamplefor604
suchanempiricallawisthemechanicalseparationbetweencrystalsandthemeltbygravity,605
whichcontrolschemicaldifferentiation.Belowathresholdcrystallinity,gravitationalsettling606
laws based on Stokes settling are generally assumed valid (Martin and Nokes 1989).607
However,itassumesthatcrystalsarefarapartandneverinteracthydrodynamicallyandthat608
thereisnoreturnflowofmelttoconservethemassfluxoveranyhorizontalsurfaceinthe609
magmabody, i.e. themagmabodyhasan infinitevolume.Themechanicsofmulti-particles610
gravitationalsettlingisquitecomplexthoughandrequiresanaccountofbothshortandlong-611
rangehydrodynamiccorrectionsevenat crystalvolume fractions significantlybelow10%612
(Koyaguchietal.1990;Koyaguchietal.1993;FaroughiandHuber2015).Anotherexample613
lies in a proper way to account for the thermal energy balance in multiphase media614
(crystals+meltforexample).Atthecontinuumscale,thetwogeneralapproachescommonly615
usedassumeeither thatover the resolutionof thenumericalmodel the twophasesare in616
thermal equilibrium (Local Thermal Equilibrium conditions or LTE) as in Simakin and617
Bindemann (2012) or that the contrast in thermal properties requires a thermal lag or618
inertiabetweenthephasesparameterizedwithinter-phaseheattransfercoefficients(Local619
ThermalNonEquilibriumconditionsorLTNE)asinDufekandBachmann(2010).Although620
the latter thermalmodel (LTNE) ismore realistic andprovidesbetter results (the current621
state-of-the-art), ithasseveral issues thatsometimesprecludes itsuse formultiphaseheat622
transfer (e.g.,KaraniandHuber, submitted).There is thereforeaneed to studymultiphase623
ReviewMUSH 4/19/2016 30
magmasatthediscretescaleanddevelopnewcontinuum-scaleconservationlawsthatdoa624
morecarefuljobwhenfilteringoutheterogeneitiesduringvolumeaveraging(seeFrontiers625
section).626
627
c)Futuredevelopmentinmodeling628
629
Apossible solution to resolve the actual thermal andmechanical interactions inmulti-630
phase magmas is to resort to granular (discrete) scale models as a complement to these631
continuumscalestudies.Thefundamentaldifferencebetweencontinuumandgranularscale632
models is that the latter explicitly solve for the mass (including chemical exchanges),633
momentum (e.g. drag) and energy (e.g. heat transfer) exchange between the different634
component through their interfaces,while the former involvesaparameterizationof these635
interactionsor, insomecases (e.g., effectivemediumtheory), relieson thedefinitionofan636
effective medium with hybrid (parameterized) properties. The granular-scale approach637
offers a significant advantage by solving a more realistic model and allows us to study638
complex feedbacksarising fromthe interactionofmultiplephases,butat thecostofheavy639
computationalrequirements.640
Several“granular”multiphasemodelshavebeendevelopedoverthelastdecadetostudy641
magma dynamics. For example, multiphase fluid dynamics modeling where crystals are642
introduced using the Discrete ElementMethod (DEM) coupled to Stokes flow solvers has643
been applied to magma chamber dynamics recently by Furuichi and Nishiura 2014 and644
Bergantz et al. 2015, consideringmostly how crystal melt mechanical interactions affects645
settling inmagmachambers.Granularscalemodels,usingthe latticeBoltzmanntechnique,646
ReviewMUSH 4/19/2016 31
havealsopermittedtostudythemigrationofexsolvedvolatilebubblesinmagmachambers647
athighcrystalcontent(seeFigure4;Parmigianietal.2011;Huberetal.2012b;Parmigianiet648
al.2014).Asmentionedabove,discretemodels(forthedispersedphase)arevaluableinthat649
theyprovideanaccuratedescriptionoftheactualphysicsthatgovernsthemass,momentum650
andenergyexchangebetweenphases,buttheyaregenerallylimitedbycomputerpowerto651
smallcomputationaldomainsandrequireupscalingstrategiestoextrapolatethedynamicsto652
thescaleofthereservoir.Upscalingmultiphasedynamicsisandwillremainagreatchallenge653
in the years to come to better constrain the chemical and dynamical evolution ofmagma654
bodiesinthecrust(seeFrontierstopicattheendofthisreview).655
656
657
ReviewMUSH 4/19/2016 32
658
Figure4.Exampleofgranularscalecalculationformultiphasemagmachamberdynamics.(a-659
c) modified from from Furuichi and Nishiara (2014) for crystal settling from a stratified660
chamberwithacrystal-freeregionatthebottomandadenser,crystal-richhorizon,atthetop,661
and(d)Parmigianietal.,2011forthemigrationofabuoyantvolatilephase inacrystal-rich662
rigidmagma.663
664
ReviewMUSH 4/19/2016 33
4 Model of magma reservoir: focusing on the “Mush” 665
Afterreviewingmostofthetechniquesandtoolsusedtostudymagmareservoirsin666
theEarth’scrust,thenextsectionwillfocusonaspecificmodelofmagmareservoirevolution,667
the so-called “Mush Model” (Bachmann and Bergantz 2004; Hildreth 2004; Huber et al.668
2009), strongly influenced by the pioneering efforts of many previous researchers (e.g.,669
Smith 1960; Smith 1979; Hildreth 1981; Lipman 1984; Bacon and Druitt 1988b; Brophy670
1991; Sinton and Detrick 1992 to cite a few). Althoughwe fully admit that this choice is671
stronglydictatedbyourpreviousexperience,webelieveithelpsprovidingaframeworkto672
many of the questions we listed in the introduction. Obviously, the model needs many673
refinements,andwewilltrytobringoutthecaveatsasweseethem.Wearealsoawareof674
the controversial aspects that remain tobe resolved (e.g.,Glazner et al. 2008;Tappaet al.675
2011; Simakin andBindeman 2012; Rivera et al. 2014; Streck 2014;Wotzlaw et al. 2014;676
Glazneretal.2015;Kelleretal.2015),buthopethatsuchareviewcanprovideastepping677
stonetobringthediscussionforward.678
679
Since volcanic rocks are, at times, relatively crystal-poor (particularly the680
compositionalextremes,basaltsandrhyolites,whereasintermediatemagmasareoftenmore681
crystal-rich; Ewart 1982), researchers have tended to draw magmas reservoirs as682
dominantly liquids (big pools of liquid magmas for both mafic and silicic units, see683
YellowstonereservoirdepictedonFigure1;figure9-14ofMcBirney1993;Irvineetal.1998;684
Maughan et al. 2002), which easily caught on in the general public’s views of magma685
reservoirs.However,asmagmasareemplacedincontactwithacoldercrust,heatlosstothe686
surroundingcrustlimitsthetimemagmasremaininamostlyliquidstateinthesereservoirs.687
ReviewMUSH 4/19/2016 34
Hence,manyresearchersarguedthatsolidificationzones(orfronts,(Marsh1981;Marshand688
Maxey1985;Marsh1989b;Marsh2002;Gutierrezetal.2013,Figure5)arelikelytodevelop689
quickly,andformacrystal-richbufferzonebetweenthehottestpart,mostliquidpartofthe690
reservoirand the subsoliduswall rocks. Since,many linesofevidencehavesuggested that691
magmas are dominantly kept as high-crystallinity bodies in the Earth’s last few tens of692
kilometers.Thesehigh-crystallinitybodiesareoftenreferred toas “crystalmushes”.Miller693
andWark (2008) defined a crystalmush as “Amixtureofcrystalsandsilicate liquidwhose694
mobility,andhenceeruptibility, is inhibitedbyahigh fractionof solidparticles.” (Miller and695
Wark 2008). This is the case for subvolcanic reservoirs (Hildreth 2004; Bachmann et al.696
2007b)inlargesilicicsystems,butalsoatMidOceanRidges(SintonandDetrick1992).The697
supporting evidences for the importance of crystal mushes stem from petrological,698
geophysical, geochemical and geological observations, aswell as thermalmodeling. These699
aredetailedbelow.700
701
ReviewMUSH 4/19/2016 35
702
703
Figure5:Crystallinityvariationsinmagmas,fromsolidustoliquidus,whichcanspanupto250704
ºC(modifiedfromMarsh1996).Thetypicalamountofheatliberatedby1kgofmagmafrom705
liquidustosolidusis~600’000Joules,ofwhich~½isfromlatentheat.706
Asthetemperaturecontrastwiththesurroundingcrustdiminishes, thecoolingrate707
alsodecreaseandmagmasspendmore timesat temperature close to their solidus (Marsh708
ReviewMUSH 4/19/2016 36
1981;KoyaguchiandKaneko1999;Huberetal.2009).Thewaningofconvectionalsoplaysa709
role decreasing the cooling rate with decreasing T. As stirring occurs, it steepens the710
temperature gradient at the edge of the body, and tend to hasten the cooling. Since711
convection only occurs at low crystallinity, it enhances the cooling near the liquidus (see712
figure 6 of Huber et al. 2009). Finally, latent heat released during crystallization provides713
energythatneedstoberemovedbeforesubsequentcoolingispossible.Ifthetemperaturevs.714
crystallinity diagram is relatively linear, latent heat is released equally over the cooling715
intervalbetweentheliquidusandsolidus,anddoesnotfavoraprolongedstateateitherthe716
low or high crystallinity range. However, the temperature vs. crystallinity relationship is717
quite complex and non-linear for many types of magmas, particularly those with near-718
eutectic points. For example, evolved high-SiO2 magmas rapidly reach the haplogranite719
eutectic and are thus characterized by a strongly non-linear phase diagram (e.g., dacitic720
magmasreachnear-eutecticconditionsat40-50vol%crystals;Bachmannetal.2002).The721
latent heat is mostly released when the magma approaches this eutectic condition and722
providesanadditionalthermalbufferingeffect,i.e.slowsdownthecoolingratesignificantly723
from that point onward (a process called “mushification” by Huber et al. 2009). Magma724
recharges canprovidea sufficient amountof enthalpy to slowor even reverse the cooling725
trendgenerallyobservedinthesereservoirs,whichcanprolongtheirexistenceatlowmelt726
fraction (Annen and Sparks 2002; Annen et al. 2006; Leeman et al. 2008; Annen 2009;727
Gutierrez et al. 2013; Gelman et al. 2014), see Figure 6 for an attempt to illustrate the728
temperature-time evolution in the warmest parts of the reservoirs. The maturation of a729
magmaticfieldthroughrepeatedintrusionsofmagmasappearstoalsoplayanimportantin730
ReviewMUSH 4/19/2016 37
priming the thermal state of the crust to host long-lived active magma reservoirs (e.g.,731
Lipmanetal.1978;deSilvaandGosnold2007a;Lipman2007;Grunderetal.2008).732
733
734
Figure 6: Schematic temperature-time diagram for a part of mature magma reservoirs735
situatedinthehottest,corezone.Notetheslowercoolingratesasthecrystalcontentincreases736
(magmaapproachingtheirsolidus).737
Evidencefromeruptedrocks:738
739
Theeruptionof large,homogeneouscrystal-richunits, suchas theFishCanyonTuff740
(Whitney and Stormer 1985; Lipman et al. 1997; Bachmann et al. 2002), the Lund Tuff741
(Maughanetal.2002)orLaPacanaTuff(Lindsayetal.2001)havealsobeenpivotalinthe742
developmentoftheMushModel(seesection4.2below).Such“MonotonousIntermediates”743
(Hildreth1981)arecommoninlargemagmaticprovinces,andunambiguouslydocumentthe744
presenceoflarge,homogeneouszonesofcrystal-richmagmasintheuppercrust,potentially745
remobilizablebyeruption.Theirhomogeneityisstriking,andrequiresarelativelythorough746
ReviewMUSH 4/19/2016 38
stirringpriortoeruption,likelytriggeredbyarechargeandremobilizationpriortoeruption747
(seebelow,Huberetal.2012aandParmigianietal.2014forreviews).748
749
Evidencefromgeophysics:750
751
Large,lowseismicvelocityzonesandconductiveMTareasbeneathactivevolcanoes752
orvolcanicprovincesalsosuggestthepresenceofnear-solidusmagmasbodies.Althoughthe753
resolutionremainspoor(hundredsofmeterstokilometers),theanomalies(bothintermsof754
electricconductivityandseismicvelocities)andthesizeofthosebodiesarenotsupportiveof755
dominantlymoltenbodies(e.g.,Dawsonetal.1990;Lees1992;Weilandetal.1995;Stecket756
al.1998;Zolloetal.1998;Masturyonoetal.2001;Zandtetal.2003;DeNataleetal.2004;757
Husenet al. 2004;Hill et al. 2009;Waite andMoran2009;Heise et al. 2010; Farrell et al.758
2014;Wardetal.2014).Estimatesofmeltrangefromafewpercenttonearly50%meltin759
some areas of the anomalies (Heise et al. 2010; Farrell et al. 2014). In addition to those760
seismic and MT anomalies, Bouguer gravity anomalies under older volcanic fields also761
suggesttheaccumulationof lowdensity,silicicrocksintheuppercrust(e.g,SRMVF,Plouff762
andPakiser 1972; Lipman1984;Drenth andKeller 2004;Drenth et al. 2012; Lipman and763
Bachmann2015).764
765
ReviewMUSH 4/19/2016 39
766
767
Figure7: Comparison between the SRMVFbatholithmodel (LipmanandBachmann, 2015; A768
andBareschematizedcross-sectionsbasedoneruptedproductsandgravitydata)andajoint769
ambientnoise-receiverfunctioninversionS-velocitymodelfortheAltiplanoregionoftheAndes770
(C;Wardetal.2014).771
Evidencefrompresenceofcumulatelithologiesinvolcanicandplutonicunits:772
773
Thepresenceofcrystal-rich,cumulateblockseruptedinvolcanicunits(Wager1962;774
Arculus andWills 1980;Heliker 1995;Ducea and Saleeby1998), aswell as largeplutonic775
massesincrustalsectionswithclearcrystalaccumulationzones(Voshageetal.1990;Greene776
etal.2006; JagoutzandSchmidt2012;Otamendietal.2012;Cointetal.2013)suggestthe777
presenceofmushzoneswithinthecrustinactivemagmaprovinces.Cumulatesignaturesare778
not only seen in deep crustal zones, but also in shallow plutonic bodies, both using bulk779
chemistry(McCarthyandGroves1979;Bachletal.2001;MillerandMiller2002;Gelmanet780
ReviewMUSH 4/19/2016 40
al.2014;LeeandMorton2015)and/ortexturalfeatures(BeaneandWiebe2012;Graeteret781
al.inpress).782
783
784
785
Figure 8: Schematic diagram of the polybaric mush model (modified from Lipman, 1984,786
Hildreth,2004,andBachmannandBergantz2008c).(1)Pre-existingcrust,(2)Uppermantle,787
(3)Feedingzoneofprimitivemagmas fromthemantle(“basalts.l.”), (4)Lowercrustalmush788
zone, with internal variability in melt content, (5) Upper crustal mush zone, (6) Melt-rich789
ReviewMUSH 4/19/2016 41
pockets in upper crust, (7) Melt-rich pockets in the lower crust, (8) Caldera structure, (9),790
Stratovolcano(e.g.,MountSt.Helens,WA,USA).791
Overthenextsections,wewilltrytorevisitthequestionsaskedintheintroduction,792
and see how mush zones (or the “Mush model”) can help accounting for the main793
observationsthatwehavelaidout.794
795
4.1 Presence of crystal-poor rhyolites, and zoned ignimbrites 796
Firstofall,weobservemanysiliciccrystal-poordepositsat thesurfaceof theEarth797
(SeeHildreth1981;Lindsayetal.2001;Masonetal.2004;Huberetal.2012a).Hence, the798
extraction of high-SiO2, cold (<800 ºC), viscous melt from crystalline residue in large799
quantities (several 100s of km3) clearly happens in many cases. In some locations, these800
crystal-poorpocketsof eruptedmagmasare ratherhomogenous (Dunbaret al. 1989;Ellis801
and Wolff 2012; Ellis et al. 2014), in others they grade into crystal-rich, typically hotter802
intermediatemagmasattheendoftheeruption(upperpartsofthedeposits;Lipman1967;803
Hildreth1981;BaconandDruitt1988a;Wolffetal.1990;Deeringetal.2011b;Huberetal.804
2012a;LipmanandBachmann2015;Figure9).805
806
Generating these eruptible silicic pockets is challenging, as extracting such viscous807
melt (up to 105-106 Pa s, evenwith severalwt% dissolved volatiles, Scaillet et al. 1998b)808
fromanetworkofmm-sizedcrystals is, atbest, sluggish (McKenzie1985;Wickham1987)809
andtheprocesscanbeeasilydisrupted.Forexample,convectioncurrentsshouldnotoccur,810
asthiswillsignificantlystirthewholemagmareservoir,andleadtore-homogenizingofthe811
crystal-meltmixture(i.e.,impedingcrystal-meltseparation).Hence,apossibility,particularly812
ReviewMUSH 4/19/2016 42
in long-lived, incrementallybuilt, sill-likemagmabodies, is thatmelt is slowly extracted by813
gravitationalprocesses(hinderedsettling,microsettling,compaction)asthemagmareaches814
the rheological lock-up (~50 vol%; Brophy 1991; Thompson et al. 2001; Bachmann and815
Bergantz 2004; Hildreth 2004; Solano et al. 2012), an extraction process potentially816
enhancedbygasfilter-pressing(SissonandBacon1999;BachmannandBergantz2006;Ellis817
etal.2014;Pistoneetal.2015).Thismeltextractionfollowinglock-upinlargemushzones818
has the advantage of (1) preventing stirring and mixing of the crystal-melt mixture by819
convectivecurrents, and (2)keeping thecrystal-poormeltpocket inawarmenvironment,820
leading to significantly reduced crystallization rate and more time for crystal-liquid821
separation.Moreover,asill-likegeometry(seeFigure8)optimizesextractionas it reduces822
the average vertical distance traveled by the viscousmelt. The interstitialmelt extraction823
frommushesseemsnottoberestrictedtoevolvedmagmas,butmayalsooccurredatmore824
mafic,lessviscouscompositions,suchasbasaltsandandesites(DufekandBachmann2010).825
826
ReviewMUSH 4/19/2016 43
827
828
Figure9: (a)Variations inSiO2andcrystal contents for ignimbrites inwesternUnitedStates829
(LC—LavaCreekTuff;T—TshigereMemberofBandelierTuff;BT—BishopTuff;WP—Wason830
ParkTuff; CR—CarpenterRidgeTuff;RC—RatCreekTuff;NM—NelsonMountainTuff;AT—831
Ammonia Tanks Tuff; FC—Fish Canyon Tuff; BC—Blue Creek Tuff, SM—SnowshoeMountain832
Tuf;MP—MasonicParkTuff).ModifiedfromHildreth1981andHuberetal.2012a;datafrom833
Hildreth 1981; Lipman2000; Lipman2006. (b) REEpatterns from crystal-poor pumices and834
crystal-rich clasts from the Carpenter Ridge Tuff,with, for reference, patterns for lamproïtic835
magmas,indicatingthatmixingwithsuchhigh-K,incompatible-element-enrichedliquidsisnot836
an option to generate the high Ba-Zr composition of the late-erupted crystal-rich clasts837
(modifiedformBachmannetal.,2014).838
839
Petrological observations in many large, zoned ignimbrites support such a magma840
reservoir model, with a cap of crystal-poor material immediately underlain by a more841
ReviewMUSH 4/19/2016 44
crystal-rich zone. Some well-exposed deposits such as the 7700 BP Crater Lake, or 1912842
Katmaieruptionsshowabruptchangesincrystallinity, fromnearlycrystal-freeearlyinthe843
eruption, to40-50vol%crystals late inthesequence,withaverysimilarmeltcomposition844
throughout the stratigraphy (Bacon andDruitt 1988a;Hildreth and Fierstein 2000; Bacon845
andLanphere2006).Otherlargeignimbritespresentmoregradualvariations,asexemplified846
byfamousBishopandBandelierTuffs(Hildreth1979;HildrethandWilson2007;Wolffand847
Ramos2014)amongmanyothers(seeHildreth1981andBachmannandBergantz2008afor848
listsofthesedeposits).Suchzonedignimbritesarebestexplainedbyeruptingamelt-richcap849
followed by partial remobilization and entrainment of a silicic cumulate from the mushy850
roots of the system, chocking the eruption (see Smith 1979; Worner and Wright 1984;851
Deeringetal.2011b;Bachmannetal.2014;Sliwinskietal.2015;Wolffetal.2015;Evanset852
al.2016).Thispartialcumulateremobilizationislikelyaconsequenceofhotterrechargeat853
thebaseofthesiliciccap,assuggestedbytextural,mineralogicalandgeochemical features854
indicativeofmixingandreheating(Andersonetal.2000;Warketal.2007;Bachmannetal.855
2014;WolffandRamos2014;Fornietal.2015).856
857
Otherprocesses, suchas incomplete/partialmixingbetweendifferentupper crustal858
magmapockets and recharge (e.g., Dorais et al. 1991;Mills et al. 1997; Eichelberger et al.859
2000; Bindeman and Valley 2003) or co-erupting physically-separated and chemically860
differentmelt-rich lenses (GualdaandGhiorso2013a)havealsobeensuggested toexplain861
the ubiquitous chemical zoning in ignimbrites. Although we do not question that such862
processesarelikelyplayingaroleingeneratingchemicalcomplexitiesintheerupteddeposit,863
these hypotheses fail to account for the presence of co-magmatic crystal-rich cumulate864
ReviewMUSH 4/19/2016 45
blocksthateruptconcurrentlywiththecrystal-poorpartsofthereservoirs(seealsoElliset865
al.2014foracaseinahot-dryrhyoliticsystem,andsection4.3below).Hence,wearguethat866
magma recharge reaching the base ofone or several crystal-poor caps above a cumulate867
zone(asdepictedinFigure8)isthemostlikelyreservoirgeometrytoexplainsuchdeposits.868
869
4.2 The “Monotonous intermediates” - remobilized mushes 870
A second conspicuous group of ignimbrites are the “Monotonous Intermediates”,871
consisting of homogeneous crystal-rich, typically dacitic units, without any evidence for872
significant crystal accumulation (Hildreth 1981; Lindsay et al. 2001;Maughan et al. 2002;873
Folkesetal.2011c;Huberetal.2012a).Suchunitstypicallydisplaycorrosiontexturesonthe874
low-temperatureminerals(quartzandfeldspars;Figure10)andpervasivereheatingpriorto875
eruption(BachmannandDungan2002;Bachmannetal.2002).Smallereruptionsofcrystal-876
richmagmas(e.g.,Montserrat,Murphyetal.2000;KosPlateauTuff,Keller1969;Bachmann877
2010a;TaupoVolcanicZone,Molloyetal.2008,Cascadearc;CooperandKent2014;Klemetti878
and Clynne 2014) also show a very similar reheating and partialmelting signal following879
rechargefromdeeper,hottermagmas(althoughmeltingevidencecanbesubtleorevennon-880
existentinsomecases).Thephysicalprocessesactinguponthisremobilizationprocesshave881
been explored by a number of papers (Bacon and Druitt 1988b; Druitt and Bacon 1989;882
Couch et al. 2001; Huber et al. 2010a; Burgisser and Bergantz 2011; Huber et al. 2011;883
Karlstrom et al. 2012). The reheating signal and the partialmelting signature inminerals884
favor amodelwhereby the reactivation results from the combination ofmelting andpore885
pressure increase in the mush in response to melting and the slow and progressive886
disaggregation of the weakened mush, a process coined as thermo-mechanical887
ReviewMUSH 4/19/2016 46
remobilization by Huber et al. 2010a. This model is also consistent with several striking888
characteristics (whole-rock homogeneity, high crystallinity, partial corrosion of minerals)889
thatsuchdepositsdisplay(Huberetal.2012a;CooperandKent2014;Parmigianietal.2014).890
891
Thermo-mechanicalremobilizationoflockedareasfollowingrechargeislikelytobea892
very common process in incrementally-built magma reservoirs. In most cases, such893
remobilizationeventswouldnotleadtoaneruption,butcouldpotentiallybeinferredfrom894
surface deformation, change in gas outputs, and/or seismic signals related to the895
emplacement of the recharge. When partial melting of crystal-rich, mostly anhydrous896
material,occurs,thenewmeltreleasedisdry,andwillimpacttherheologicalresponseand897
phase diagram of the newly producedmixture (Evans and Bachmann 2013; Caricchi and898
Blundy 2015; Wolff et al. 2015). As drier melt increases the temperature of mineral899
precipitation (e.g., JohannesandHoltz1996), theamountofmeltingwill tend tobe rather900
limited inmost cases (Huber et al. 2010a;Wotzlaw et al. 2013). Hence, the condition for901
eruptionduring remobilizationmight onlybe reachedwhensignificant heat andvolatiles902
(mainlyH2O) are injected by the incoming recharge. Exactly howmuch heat and volatiles903
need to be injected strongly depends on a number of factors (including relative size of904
rechargeandmush,geometry,compositionsofmagmaticendmembers,averagecrystallinity905
ofthemush,…),whichwillvaryfromcasetocaseandaredifficulttopredict.906
907
ReviewMUSH 4/19/2016 47
908
Figure10:Phasemapsofcrystal-richignimbrites,bothremobilizedcrystalmushesatdifferent909
stagesofrejuvenation;theMasonicParkTuffnolongerhasanysanidineandshowsonlytiny910
quartz microcrysts, whereas the Fish Canyon Tuff still shows large, albeit highly resorbed911
quartzandsanidinephenocrysts(Bachmannetal.2002).Inbothcases,plagioclaseandmafic912
crystals(hornblendeintheFCT,andpyroxeneintheMPT)showreversezoning(Lipmanetal.913
1996;BachmannandDungan2002).914
915
ReviewMUSH 4/19/2016 48
4.3 The unzoned, crystal-poor to intermediate deposits 916
There is a third type of ignimbrite that commonly appears in volcanic sequences,917
particularlyinareaswheremagmatismisrelativelydry(hotspotorriftenvironmentssuch918
as Yellowstone – SnakeRiver Plain or TaupoVolcanic Zone). In such cases, homogeneous919
ignimbriteswithcrystalcontentsontheorderof10-20%arecommonplace(Dunbaretal.920
1989;Nashetal.2006;EllisandWolff2012;Ellisetal.2013).Ubiquitousinsuchunitsare921
mm to cm-sized glomerocrysts of pyroxene-plagioclase-oxides (Figure 11). These922
glomerocrystsaremuchmoremafic (whenanalyzed inbulk) than thebulk rocks theyare923
found in,andentirely lacksanidineandquartz,while theyare foundasphenocrysts in the924
hostunits.However, thechemicalcompositionsof theirpyroxenesandplagioclasecrystals925
areidenticaltotheindividualphenocrystsaroundthem.Theseglomerocrysticpyroxeneand926
plagioclasealsoshowveryevolvedREEpattern,suggestinggrowthfromrhyoliticmelts(Ellis927
etal.2014).928
929
ReviewMUSH 4/19/2016 49
930
Figure 11: Glomerocrystswith cumulate characteristics found in ignimbrites from the Snake931
RiverPlain(modifiedfromEllisetal.2014)932
Within the framework of the mush model, such deposits are best understood as933
pockets of melt-dominated regions in relatively hot/refractory mushes built in such dry934
magmaticenvironments.Uponrechargefrombelow,thesedrymushesarelikelynottomelt935
aseasilyastheonesthatcontainsanidineandquartz(asfoundinwetter,coldersubduction936
zoneenvironments).Hence, thezoningproducingbypartialmeltingofcumulatesdoesnot937
happen, and thedeposits remainhomogenous.Asgas sparging canalsoplayan important938
ReviewMUSH 4/19/2016 50
role in mush defrosting (Bachmann and Bergantz 2006; Huber et al. 2010b), mushes in939
magmaticallydryenvironmentsaremoredifficult to remobilizebecauseexsolvedvolatiles940
fail to reach the critical volume fraction required for efficient heat transfer by advective941
transport(Huberetal.2010b),andproducemostlythisremarkabletypeofunzoned,crystal-942
poortointermediatedeposits(Ellisetal.2014;Wolffetal.2015).943
944
4.4 Chemical fractionation in mushy reservoirs: the development of 945compositional gaps in volcanic sequences 946
Compositionalgaps,orthepaucityoferuptedproductswithinarangeofcompositions,947
arecommonplaceinvolcanicsequencesandcalledtheBunsen-Dalygaps,inhomagetoearly948
workfromBunsen(in1851)andDaly(in1925)onIcelandandAscensionIsland.Suchgaps949
canbeseenindifferentelements(majorandtrace), inallseries, includingtholeiitictrends950
(e.g., Thompson 1972) and subduction zones (Brophy 1991; see Figure 11). Possible951
hypothesestoexplainthesegapsdominantlyrevolvearoundthreemainlinesofreasoning;952
(1)twomainmagmatypes(onemafic,onefelsic/silicic)aregeneratedintheupperpartsof953
our planet, mostly bymeltingmantle and crustal components (e.g., Bunsen 1851; Chayes954
1963;ReubiandBlundy2009),(2)twomagmatypesaregeneratedby liquid immiscibility955
(e.g., Charlier et al. 2011) and (3)magma evolution is dominated by crystal fractionation956
from mafic parents (generating a continuum of melt composition) but due to some957
mechanical trapping (potentially enhanced by non-linear temperature-crystallinity958
relationships),magmareachingthesurfacearedominantlyclusteredatsomecompositions959
(Marsh 1981; Grove and Donnelly-Nolan 1986; Brophy 1991; Bonnefoi et al. 1995;960
ReviewMUSH 4/19/2016 51
Francalanci et al. 1995; Grove et al. 1997; Freundt-Malecha et al. 2001; Thompson et al.961
2001;DufekandBachmann2010;Melekhovaetal.2013).962
963
Althoughthesehypothesescanallplayarole indifferentmagmaticsystemsaround964
theworld, themechanical trappingofmelt, as seenwithin the contextof themushmodel,965
shouldbedominantinlargemagmaticprovinceswheresuchgapsareobvious(oceanislands,966
subduction zones in thin oceanic crust or thin continental crust such as the Aegean and967
Taupovolcaniczones)andcrustalmelting/liquidimmiscibilityarelikelynotefficient.The968
keymechanicalreasoningfortrappingmeltisthefollowing:atlowmeltfractions(0to~50969
vol% crystals),melt and crystals are not easily separable, due to (1) the stirring effect of970
magma convection and (2) the short time that these magmas spent at low crystallinities971
(Marsh1981;KoyaguchiandKaneko1999;Huberetal.2009;DufekandBachmann2010).972
Hence, melts are dominantly extracted from the crystal cargo only after significant973
crystallization, showing then a composition that is very different from the mixture974
composition(Deeringetal.2011a).Asanexampleofageologicalsettingwheretheamount975
of crustal contamination shouldbevery limited (Sliwinski et al. 2015), the compositionof976
erupted magmas in Tenerife displays 3 principal modes in SiO2 (mafic, intermediate and977
felsicmagmas) likely indicatingmelt compositions released from(1) themantle (themost978
primitive), (2) the lower crustal differentiation zone (intermediate magmas) and (3) the979
upper crustal differentiation zone (the most felsic magmas). Although it was claimed by980
Melekhovaet al. (2013) that themagnitudeof thegaps shoulddiminishwith time (on the981
basisofpurelythermalcalculations),thisdoesnotappeartobetrueinmagmaticprovinces982
aroundtheworld(e.g.,Tenerife;Sliwinskietal.,2015).983
ReviewMUSH 4/19/2016 52
984
985
986
Figure 12: (a) Compositional groups observed in the Kos-Nisyros volcanic center (Eastern987
Aegean; see Pe-Piper and Moulton 2008 and Francalanci et al. 1995). (b) Tri-modality in988
compositionsofvolcanicrocksfromTenerife(ModifiedfromSliwinskietal.2015).989
4.5 The volcanic-plutonic connection 990
How compositionally and temporally-related (i.e., same age range, see section on991
timescales below) volcanic and plutonic units fit onto a common framework has been992
actively debated for nearly 2 centuries (discussion started by James Hutton at the 18th993
century, andpushed further in classicalbooksbyLyell1838;Daly1914;Bowen1928and994
papersormemoirssuchasRead1948;Read1957;Buddington1959;HamiltonandMyers995
1967; Pitcher 1987). Several recent review papers summarize the main issues at play996
(Bachmann et al. 2007b; de Silva and Gosnold 2007a; Lipman 2007; Glazner et al. 2015;997
ReviewMUSH 4/19/2016 53
Keller et al. 2015; Lipman and Bachmann 2015). Focusing on felsic/silicicmagmas (mafic998
plutons are clearlymostly considered cumulates for decades; e.g.,Wager et al. 1960), the999
main hypotheses revolve around whether intermediate to silicic plutons are mostly the1000
expression of crystallized melts (“failed eruptions”, i.e., have not undergone significant1001
crystal-liquid separation), or cumulate leftovers (“crystal graveyards”) from volcanic1002
eruptions (those two endmember hypotheses not being mutually exclusive in plutonic1003
complexes containing multiple facies). Textural analysis of plutonic lithologies and trace1004
element geochemistry (in both bulk rock and minerals) should be the two main lines of1005
arguments to differentiate between these competing hypotheses. If crystal accumulations1006
occursinareasofthecrust,1007
• Compatible trace elements should show significant increase in their1008
concentrations, while incompatible elements should remain low (e.g.,1009
Mohamed1998;Bachletal.2001;Wiebeetal.2002;Kamiyama2007;Deering1010
andBachmann2010;Turnbulletal.2010)1011
• Plutonic rocks should show some mineral orientations or preferential1012
alignment/foliation (e.g.,Wager et al. 1960; Arculus andWills 1980; Shirley1013
1986; Seaman 2000) related tomagmatic processes (e.g., hindered settling1014
and/orcompaction),whichwilltendtoorientanisotropically-shapedcrystals1015
astheyaccumulate.1016
1017
ReviewMUSH 4/19/2016 54
1018
Figure13:Exampleofacross-sectionthroughawell-exposedpluton(Searchlightpluton,NV),1019
showing areas of rich in crystallizedmelts and areaswith cumulate characteristics, but still1020
containingtrappedmelt(modifiedfromBachletal.2001;Gelmanetal.2014).1021
1022
Despite several attempts to look in details at this issue, this topic remains1023
controversial(seedeSilvaandGregg2014;Glazneretal.2015;LipmanandBachmann2015).1024
ReviewMUSH 4/19/2016 55
Therootofthecontroversymaylargelystemfromthefactthattheamountofcrystal/melt1025
segregation is less important in evolved (silicic) magmas compared to than more mafic1026
compositions (i.e., more trapped melt component in the intermediate to silicic crystal1027
cumulates)due largely to viscositydifference;Bachmannet al. 2007b).Hence, silicicunits1028
havemoresubtlegeochemicalor textural signaturesofcrystalaccumulation(ormelt loss)1029
than their mafic counterparts, and can easily be overlooked (see Gelman et al. 2014).1030
However, although recent publications involving compilations of geochemical data from1031
large databases (e.g., Glazner et al. 2015; Keller et al. 2015) cannot clearly differentiate1032
volcanic from plutonic compositions at the felsic/silicic end of the spectrum, other1033
compilations do see significant variabilitieswith volcanic units being on average richer in1034
SiO2 (Lipman 1984; Halliday et al. 1991; Lipman 2007; Gelman et al. 2014; Deering et al.1035
2016).Recentstudiesonfocusingonspecificfieldexamplesshowthatseveralintermediate1036
tosilicicplutoniclithologieshavehighcompatible/lowincompatibleelementconcentrations1037
inbulkrock(althoughsuchunitsclearlystillhavesignificanttrappedmeltcomponents;e.g.,1038
Bachl et al.2001;Barneset al.2001;DeeringandBachmann2010;LeeandMorton2015;1039
Figure13).Additionally,detailedtexturaldata,usingElectronBackscatteredElectron(EBSD)1040
techniques, on non-metamorphosed granitoïds (i.e., observedmineral orientationmust be1041
magmatic) indicate crystal alignment compatiblewith compaction/hindered settling, even1042
forveryviscousmagmacompositions(BeaneandWiebe2012;Graeteretal.2015).1043
1044
4.6 The high eruptability of rhyolitic melt pockets 1045
Whilehigh-SiO2 rhyolitesarenot rare in thevolcanic record, including severalvery1046
largeunits(>100km3;Lipman2000;Christiansen2001;Masonetal.2004),granitessensu1047
ReviewMUSH 4/19/2016 56
stricto appear much less commonly. The upper crustal plutonic record is dominantly1048
granodioritic/tonalitic in composition (Taylor andMcClennan1981;Rudnick1995).When1049
compiling data from large geochemical database, such as the NAVDAT1050
(http://www.navdat.org),onenoticesthatlowSrrocksare,relativelyspeaking,muchmore1051
abundant in the volcanic realm than in theplutonic record (Parmigiani et al. Inpress), an1052
observationalreadydiscusseda¼ofacenturyagoonamuchsmallerdatabase(Hallidayet1053
al.1991;CashmanandGiordano2014).1054
1055
A possible explanation for the unusually high volcanic/plutonic ratio of evolved1056
magmas is the fact that rhyolites are generated and stored in the upper crust (Tuttle and1057
Bowen1958;Gualda andGhiorso2013b;Ward et al. 2014; LipmanandBachmann2015),1058
wherevolatiles can exsolved inquantity. If exsolvedmagmatic volatiles can accumulate in1059
suchmeltpools, itwill render themhighlyeruptible(increasing thegravitationalpotential1060
energyof themagma)andwill tend topromotemorevoluminouseruptions (Huppertand1061
Woods, 2002). As a consequence itwill also lead to a deficit in the plutonic record.Using1062
multiphase numerical simulations of exsolved volatile transport in magma reservoir,1063
Parmigiani et al. (in press) have shown that bubbles tend to accumulate in crystal-poor1064
environments. In crystal-rich environments, the volume available for the exsolved volatile1065
phase is significantly reduced (porosity) by crystal confinement and promotes bubble1066
coalescence and the formation of buoyant fingering pathways. Once the pathways are1067
established,theveryviscousmeltdoesnotlimitthemigrationefficiencyofthevaporphase1068
andtransportisefficient.Incontrast,incrystal-poorenvironment,fingeringchannelsarenot1069
stableandbreakintobubblesundertheactionofcapillaryforces.Discretebubblescanonly1070
ReviewMUSH 4/19/2016 57
riseasfastastheviscousmeltcanbemovedoutoftheirway,whichsignificantlyreducesthe1071
migrationefficiencyofexsolvedvolatilesincrystal-poormagmas.Asaresult,bubblestendto1072
accumulateintheconvectingrhyoliticcap,providingadditionalpotentialenergytodriveor1073
sustainfutureeruptions.1074
1075
The accumulation of a buoyant volatile phase in these high SiO2melt pools favors1076
largeeruption,butitisunlikelytoprevententirelytheformationplutoniccounterpartsasit1077
onlybringsthesemagmasclosertoacriticalstate.Infact,zonesofevolvedhigh-SiO2granites1078
doseldomoccur inplutonicseries.Theyappeartobemostlypresent intheupperpartsof1079
plutons, near the roof. Typical examples of such evolved pockets have been described in1080
plutonsfromNevada(Bachletal.2001;Barnesetal.2001;MillerandMiller2002),Klamath1081
Mountain, CA (Coint et al. 2013), Sierra Nevada batholith, CA (Putirka et al. 2014) and1082
PeninsularRangeBatholith,Mexico(LeeandMorton2015).1083
1084
4.7 Pluton degassing and volatile cycling 1085
The chemical composition of the atmosphere is tied to some extent to magmatic1086
degassing (e.g., CO2 and H2O cycles). As magmas are dominantly forming plutons1087
(plutonic/volcanicratiosaretypicallyatleast5:1to10:1,andpossiblyevengreaterinsome1088
areas;Crisp1984;Whiteetal.2006;Wardetal.2014),thecycleofdegassingandoutgassing1089
inplutonsexertsan importantcontrolonthechemistryof thesurfacereservoirsonEarth.1090
Theprotractedperiodsofstorageandslowcrystallizationathighcrystallinitypredictedby1091
the mush model are prone to lead to particularly efficient magma degassing at shallow1092
depths.Insuchslowlycooledcrystal-richenvironments,exsolvedmagmaticvolatilebuildup1093
ReviewMUSH 4/19/2016 58
in the mush by second boiling (exsolution produced by the crystallization of dominantly1094
anhydrousminerals),andprogressively fillmoreof theconstrictedporespaceleadingtoa1095
more efficient outgassing (Parmigiani et al. 2011; Huber et al. 2012b; Huber et al. 2013).1096
Oncetheporespace,andmorespecificallytheporethroats,aresignificantlyreducedinsize1097
(downtothescaleofafewmicrons),capillarystressescanevenbecomelargeenoughforgas1098
pathwaystodeformlocallythegranularstructureinthemushandvolatile-filled“dikes”may1099
finalize the outgassing at large crystal fractions (>80% vol; Holtzman et al. 2012;1100
Oppenheimeretal.2015),possibly leadingtothe formationof theubiquitousapliticdykes1101
seeninplutons(e.g.,JahnsandTuttle1963;Candela1997).Ineithercase,thecombinationof1102
high crystal-content and increasing exsolved volatiles volume fraction can lead to the1103
formation of efficient degassing pathways even during quiescent periods (sometimes1104
potentiallypreservedasresidualporosityingranites,e.g.,Dunbaretal.1996;Edmondsetal.1105
2003;LowensternandHurvitz2008).1106
1107
4.8 The Excess S paradox associated with the eruption of silicic arc magmas 1108
Themassbalanceofvolatilesreleasedduringvolcaniceruptionscanprovidevaluable1109
insights into the state of shallow magma reservoirs prior to the eruption. As such, the1110
mismatchinSmassbalancebetweenpetrologicalinferences(i.e.,comparingtheScontentof1111
pre-degassed melt inclusions and fully-degassed matrix glass) and remote sensing1112
spectroscopy or sulfur output estimated from ice core data can provide additional clues1113
aboutthedynamicsthatprevailinmagmachambersandmorespecificallyaboutthefactors1114
thatcontrolvolatileexsolution.ThenotionofExcessSreferstotheunderestimationofthe1115
sulfuroutputfrompetrologicalconstraints(meltinclusionrecord)duringaneruption.This1116
ReviewMUSH 4/19/2016 59
“ExcessS”paradoxhasbeenevidentsincetheeruptionofElChichoninMexico(Luhretal.1117
1984)anddescribedindetailsfortheeruptionofMtPinatuboin1991.AtPinatubo,remote1118
sensingmethodsestimated theSoutput tonearly20Mt(e.g.,Sodenetal.2002)while the1119
petrologicalmethod provided an estimate smaller by a factor of 10 (Gerlach et al. 1996).1120
Sincethesetwoeruptions,thereleaseofSinexcesstopetrologicestimatesseemstobemore1121
therulethantheexception,especiallyforsilicicmagmasinarcs(seeFigure14andWallace1122
2001;Shinohara2008).1123
1124
Figure 14: Excess Sulfur is based on the mismatch between the SO2 flux measured during1125
volcanic eruptions (y-axis; typically done by spectroscopic methods or ice core data) and1126
petrological estimates based on the difference in S content between melt inclusions and1127
interstitialglass,estimatingtheamountofSreleasedbytheeruptivedecompressionprocess(x-1128
axis).1129
ReviewMUSH 4/19/2016 60
1130
Althoughmultiplehypotheseshavebeensuggestedtoaccount forthisExcessS(see1131
Gerlach et al. 1996 for a review), the presence of a S-rich exsolved volatile phase in the1132
magmareservoir seems tobe themost commonlyacceptedpostulate (Gerlachetal.1996;1133
Scailletetal.1998a;Wallace2001;Shinohara2008).Crystallization-driven(secondboiling)1134
exsolution in a shallow magma reservoir can generate significant excess S where the S1135
trapped by vapor bubbles during crystallization is not accessible to melt trapped1136
subsequently as inclusion in crystal hosts. Although second boiling is bound to play an1137
important role on generating Excess S in crystal-rich magmas, in crystal-poor silicic1138
eruptionsthedeficitinSinmeltinclusionsrequiresanalternativeprocess.Inthelightofthe1139
previous section, accumulation of exsolved (S-rich) volatile bubbles in the erupted, low1140
crystallinity portions of magma reservoirs would provide a closure to the problematic1141
missingSincrystal-poorsilicicmagmas,Thesebubbles(poorly-constrained,butlikelyupto1142
20-30ofpercentbyvolume)canbeextremelyrichinS,duetotheveryhighaffinityofSfor1143
theexsolvedvolatilephase(Zajaczetal.2008).Hence,themushmodel,predictingefficiently1144
degassedcrystal-richzonesandgas-charged,highlyeruptiblepocketsofmagma,providesa1145
consistent framework to explain the missing source of S necessary to close the volatile1146
budgetforcrystal-poorunits.1147
1148
4.9 Caldera cycles 1149
Caldera-forming events typically happen after long periods of maturation in long-1150
lived magmatic provinces during which andesitic volcanism dominates for up to several1151
millionsofyears(Lipman,2007;deSilvaandGosnold2007b;Grunderetal.2008;Deeringet1152
ReviewMUSH 4/19/2016 61
al. 2011a).During this andesite-dominatedperiod, the crust initiallywarmsup to become1153
more amenable to host silicic magma reservoirs in the mid to upper crust (Jellinek and1154
DePaolo2003;deSilvaandGregg2014).Oncethismaturestageisreached,itisnotrareto1155
seeseveral,caldera-formingeventsoccurringinrelativelyshorttimespans(≈2-3Myr;multi-1156
cycliccalderasystems;Hildrethetal.1991;Grahametal.1995;Christiansen2001;Lipman1157
and McIntosh 2008; Lipman and Bachmann 2015). During such caldera cycles, magmas1158
erupting shortly (≈5-30 kyr) prior to the caldera-forming event typically appear to be1159
compositionally similar to the climactic event (e.g., Bacon and Druitt 1988b; Bacon and1160
Lanphere 2006; Bachmann et al. 2012), whereas the post-caldera magmas appear more1161
mafic,anddrier(Shaneetal.2005;Bachmannetal.2012;Gelmanetal.2013a;Barkeretal.1162
2014; Figure 14). These petrological shifts can be explained by the fact that the left-over,1163
crystal-rich (mush) portion of the magma system following the eruption will be strongly1164
affectedby thecaldera-formingevent (Hildreth2004).As thoseeruptions typically lead to1165
significantdecompressionof theunderlyingcrustalcolumn(potentiallyup to50-100MPa,1166
accountingfortheoverpressurenecessaryfortheeruptiontostartandtheredistributionof1167
massfollowingtheremovalofmuchoftheeruptiblepartsofthereservoir,seeBachmannet1168
al.2012),somerapidandsignificantdegassingandcrystallization isexpected inthemush,1169
particularly if it isnear-eutecticandvolatile-saturated(Bachmannetal.2012).Formushes1170
that were volatile-saturated prior to the decompression, the caldera eruption will likely1171
promote the rapid formationofgaschannels resulting indeepgas release.Hence, the left-1172
overmush is expected to becomemore crystalline (decompression-driven crystallization)1173
andmoredegassed than itwasbefore the calderaeruption (Degruyteret al. 2015). Itwill1174
ReviewMUSH 4/19/2016 62
takeanotherlongmaturationstageforthesystemtobeprimedforanewcalderaeventwith1175
ashallow,gas-charged,evolvedmagmabody.1176
1177
1178
Figure 15: A caldera cycle recorded by changes in temperature, oxygen fugacity, bulk rock1179
composition,andmineralogy in theKos-Nisyros volcanic system, easternAegean.Pre-caldera1180
units (Kefalos domes and pyroclastic units) show highly evolvedmagma compositions (high-1181
SiO2 rhyolites), low temperature, oxidized and water-rich conditions, similar to the caldera-1182
formingevent(KosPlateauTuff,KPT).FollowingtheKPT,Nisyrosvolcanobuiltup,generating1183
moretypically lessevolvedmagmas, includingtwo largerhyodaciticunits (lowerPumiceand1184
ReviewMUSH 4/19/2016 63
Upper Pumice), with drier, more reduced compositions, and hotter magma temperatures.1185
SimilarcycleshavebeensuggestedfortheTaupoVolcanicZone,inNewZealand(modifiedfrom1186
Bachmannetal.2012).1187
5 Timescales associated with magma reservoirs 1188
How long does a magma body stay above the solidus in the Earth’s crust (i.e.,1189
potentiallyactive)remainsoneofthekeyquestionsinmagmaticpetrologyandvolcanology.1190
The longevity, of course, impacts the extent of magmatic differentiation (including ore1191
formation)andtheeruptivevolumethatareavailableatanygiventime.Asdiscussedabove,1192
magmatic reservoirs aremostly kept as high-crystallinity regions above the soliduswhen1193
active, but some controversies remain as to how long the system remains in such amush1194
state (with estimates from a few 1’000s to more than 1’000’000 years). The crux of the1195
debate lies in the fact that different analytical techniques provide different answers, and1196
likely date different processes. Zircon dating of silicic plutons and volcanic rocks record1197
extendedcrystallizationhistories, ranging fromtensof thousands toseveralmillionsyears1198
(Reidetal.1997;BrownandFletcher1999;Lowensternetal.2000;ReidandCoath2000;1199
Charlieretal.2003;Schmittetal.2003;Colemanetal.2004;VazquezandReid2004;Bacon1200
and Lowenstern 2005; Charlier et al. 2005; Simon and Reid 2005; Bindeman et al. 2006;1201
Matzeletal.2006;Bachmannetal.2007a;Charlieretal.2007;Milleretal.2007;Walkeretal.1202
2007;Reid2008;Claiborneetal.2010;Schmittetal.2010b;Klemettietal.2011;Stormetal.1203
2012;Walkeretal.2013;Wotzlawetal.2013;Chamberlainetal.2014b;Stormetal.2014;1204
Wotzlaw et al. 2014). In contrast, crystal size distributions (CSD; Pappalardo and1205
Mastrolorenzo2012),anddiffusiontimescales(seeDruittetal.2012andthecompilationof1206
ReviewMUSH 4/19/2016 64
data in Cooper and Kent 2014) are typically much shorter (typically months to a few1207
hundredsofyears).1208
1209
Asmostelementsusedindiffusiontimescalemodelingmoverelativelyfast(e.g.,Fe-1210
Mg in mafic minerals, Ti in quartz, Sr and Mg in plagioclase, Li in zircon, …), it is not1211
surprising that preserved zoning patterns in such elements indicate relatively short1212
timescales. Using simple scaling, one can provide a rough estimate ofmaximum timescale1213
that diffusion re-equilibrationwouldprovide if one knows the size of the crystals and the1214
diffusioncoefficients(time~R2/D,whereRistheradiusandDthediffusivity).Elementsthat1215
are diffusing slower (REE, Ba) can be used to obtain longer timescales (e.g., Morgan and1216
Blake 2006; Turner and Costa 2007), but, in such cases, periodic resorption, concurrent1217
crystalgrowthand3-Deffectsassociatedwith the finitesizeof thehost lead tosignificant1218
complications in estimating time. For example, growth of feldspars in the Yellowstone1219
magma reservoirs (Till et al. 2015) demonstrably led to “diffusion-like” profiles that look1220
similarforelementsthatarediffusingatverydifferentrates.Similarly,CSDstudiestypically1221
assume lineargrowthrates (nopauses incrystallization,noresorptionevent),withvalues1222
obtained from experiments (hence typically faster than what actually happens in silicic1223
magmareservoirs).Hence,crystalsizedistributionsprovidealowerbound,andsometimes1224
stronglyunderestimated,timescale.1225
1226
The short timescales obtained by diffusion modeling are best interpreted as1227
reactivation/remobilization/mixingtimescales(e.g.,Martinetal.2008;Matthewsetal.2012;1228
Tilletal.2015).They,however,donotprovideatimescaleofmagmareservoirgrowthand1229
ReviewMUSH 4/19/2016 65
storageinthecrust.Forsuchinformation,thezirconagedistributions,orbulkU/Th/Ra/Pb1230
ages likely provide more reliable estimates (Reid et al. 1997; Cooper and Reid 2003;1231
Bachmannetal.2007a;Turneretal.2010;CooperandKent2014;Guillongetal.2014).The1232
differencebetweeneruptionage(estimatedusingtheyoungzirconpopulationortheAr/Ar1233
age when available) and the oldest co-genetic zircons (i.e, antecrysts, see Bacon and1234
Lowenstern2005;Milleretal.2007foradefinition) is typicallyat least104-105years(see1235
Costa 2008; Reid 2008; Simon et al. 2008; Bachmann 2010b for reviews on the topic).1236
Xenocrysts(foreigncrystalscomingfromunrelatedwallrocklithologies)canalsooccur,but,1237
in some cases, they can be isolated and removed from the dataset (as they can be1238
significantly older, plot off theConcordia and/orhavedifferent trace element chemistries;1239
Miller et al. 2007; Lukács et al. in press). Of course, the presence of older but co-genetic1240
zircons(antecrysts)doesnotmeanthatthesystemremainedabovethesolidusforthewhole1241
time; some parts of the system could have reached the solidus, and later recycled by1242
reactivation events (Schmitt et al. 2010a; Folkes et al. 2011a).Hence, physicalmodels are1243
neededtoaddressthisissue.1244
1245
Numericalmodelsof thethermalstateofsuchsystemsusuallyagreewithrelatively1246
long timescales of tens to hundreds of thousands of years, particularlywhen they include1247
incrementalrechargeatrelativelyhighfluxes(e.g.,Annenetal.2008;Gelmanetal.2013b).1248
Moreover, it is very costly, both in termsof volatiles andenergy, to reactivate sub-solidus1249
plutons;nearlyallvolatileelements(includingCO2andH2O;CaricchiandBlundy2015)and1250
all latentheathasbeenlosttothesurrounding.Ifthesubsolidusmaterialhastobemelted1251
again, the thermalbudget required involvesnotonly the sensible and latentheat loss, but1252
ReviewMUSH 4/19/2016 66
also a large fraction of energy wasted on reheating solid material that will not undergo1253
melting (Dufek and Bergantz 2005). The assimilation of these devolatilized sub-solidus1254
portionsofthebodywillalsoinduceadepletionofvolatilecontentinthereservoir.Froma1255
mechanical standpoint, entrainment/recycling of material that is not completely solid is1256
muchmore likely, as itwill disaggregatemore easily, particularly if some localmelting at1257
grainboundariesisinvolved(Beardetal.2005;Huberetal.2011)1258
1259
In summary, the periodic recharge of magma at reasonably high fluxes (>10-4-10-31260
km3/yr; Annen et al. 2008; Gelman et al. 2013a; Gelman et al. 2013b; Karakas and Dufek1261
2015)islikelytomaintainatleastpartsofsilicicmagmareservoirsintheEarth’scrustarein1262
amushstateforperiodsextendingtoatleastseveral100softhousandsofyears,eveninthe1263
upperpartofthecrust(8-10kmdepth).Shortertimescales,obtainedwithothertechniques1264
(particularlydiffusionmodeling)mainlyrefertoperiodsofreactivationfollowingsignificant1265
heatandmassadditionintothereservoirs(CooperandKent2014;Tilletal.2015).Hence,1266
crystal/liquid separation is likely to have enough time to occur, despite being sluggish, to1267
some extent in those reservoirs, driving differentiation towards more evolved, and more1268
eruptible crystal-poor magma pods (e.g., Bachmann and Bergantz 2004; Hildreth 2004;1269
Bachmann and Bergantz 2008c; Lee et al. 2015).We note that those thermalmodels are1270
lacking the mechanical part of the energy budget (overpressurization during recharge,1271
depressurizationduringeruption),whichcanhaveasignificant impactonthestabilityand1272
durationofreservoirs(DegruyterandHuber2014;Degruyteretal.2015)andthefeedbacks1273
with crustal rheology (Gregg et al. 2013; de Silva and Gregg 2014). For example the1274
exsolutionofvolatilesaffect theeffective thermalpropertiesof themagmaby reducing its1275
ReviewMUSH 4/19/2016 67
thermalcapacityandconductivity(Huberetal.2010b),andconsuminglatentheat.Wenote,1276
however,thataddingthismechanicalparttothemodelsisunlikelytosignificantlyshorten1277
thelifetimesofthereservoirs.1278
1279
6 Frontiers in our understanding of magma chamber evolution 1280
1281
Over the last paragraphs, we have tried to assemble many important questions in1282
volcanology/petrology into a coherent framework. The Polybaric Mush Model (Figure 8)1283
provides a context to explain several seemingly unconnected observations, such as the1284
geophysical imagingofcrystal-richzonesinmagmaticallyactivezonesatdifferentlevels in1285
the crust, the chemical differentiation of magmas dominated by fractional crystallization1286
(withsomeassimilation,explainingsomeofthevariabilityinisotopicdata)ofmaficparents,1287
the production of compositional gaps in volcanic series, the presence of cumulates in the1288
plutons records, and the volatile mass balance in shallow reservoirs. However, there are1289
manyquestions thatremaintobeanswered,andthenextsectiontries tooutlinessomeof1290
thechallengesthatourcommunityfacesintheyearstocome.1291
1292
At themost fundamental level, thegoal is tocontinuedevelopingamore integrated1293
picture between physical models, geophysical/geodetical inversions and1294
petrology/geochemistry. In particular, we should tend to obtain amulti-phase andmulti-1295
scale(timeandspace)pictureofmagmaticsystems,fromtheformationoftheprimarymelts1296
to their final resting place in the crust or at the surface (including interactions with the1297
atmosphere).Inordertoreachsuchanambitiousgoal,wewouldneed,amongmanythings:1298
ReviewMUSH 4/19/2016 68
• To revisit the information that can be extracted from the inversion of1299
geophysical datasets. Thebest resolution that one can obtain fromamagma1300
body at depth is much lower than most structures of interest in these1301
dynamical environments. As such, it is important to understand how the1302
implicit filteringoperatesandhowit impactsthesetofquestionsthatcanbe1303
logicallyaddressedwiththesestudies.Forexample,ifthetargetoftheanalysis1304
is to estimate melt fraction from Vp/Vs tomography, even with good1305
experimental calibration, one is left towonderwhat the estimates of amelt1306
fractionatthescaleofhundredsofmeterstoevenkilometersreallymean.Is1307
theoutcomeof the inversiontobeunderstoodasavolumetricaverage(as is1308
commonly assumed)? The effective mechanical properties of heterogeneous1309
media, which is what one measures through inversions, are generally quite1310
different from a volumetric average. For complex, but structured,1311
heterogeneousmedia,theeffectivepropertiesinferredfromelasticproperties1312
for example, result from a complex non-linear optimization process. For1313
instance, it isquitepossible that theeffectivemediumelasticproperties that1314
oneretrieves fromtomographyaredominantlycontrolledbyheterogeneities1315
thatarevolumetricallysecondary.Wecertainlyneedmoreefforttorelatethe1316
best-fit results of these inversions to the physical reality of complex1317
multiphasemagmabodies.Thisstartswithabetterunderstandingoftherole1318
ofsubgridscalestructuresontheeffectivepropertiesattheresolutionofthe1319
inversion.1320
ReviewMUSH 4/19/2016 69
• Tocontinuedevelopingandimprovingourinterpretationoftracersforratesof1321
processes in magmatic systems. For example, it is necessary to improve1322
precision and spatial resolution of mineral geochronology; and do more1323
diffusionmodelingofmeasuredgradients todetermine timescales, and focus1324
on what they mean. It also becomes possible to use stable and radiogenic1325
isotopes to constrain thermodynamics and kinetics, although the most1326
substantialeffortinthisdirectionsofarrelatestomaficmagmas(Richteretal.1327
2003;Watkins et al. 2009b; Huang et al. 2010; Savage et al. 2011).We also1328
need better constraints on possible growth rates of minerals and bubbles.1329
Dissolution events are transparent to the present chronometers and leaves1330
hiatus in the temporal evolution of magma bodies that are impossible to1331
quantify at the present time. Canwe find kinetic tracers thatwould provide1332
information about the duration and frequency of resorption/dissolution1333
events?1334
• Tobetter constraindisequilibrium/kinetic effects inmagma reservoirs.Most1335
of the petrology and trace element partitioning among phases in magma1336
reservoirs assumes at least a local equilibrium. The mere fact that1337
crystallization(andsometimesdissolution)takesplacerequiresafinitedegree1338
of disequilibrium, even over small (crystal sizes) scales. In order to relate1339
dynamical processes to the rock record, a kinetic framework is necessary.1340
Thereareampleinformationtominefromheterogeneitiesanddisequilibrium;1341
these clueswill becomecrucial in testingdynamicalmodels andestablishing1342
whatsetofprocessescontrolsthetemporalevolutionofthesereservoirsover1343
ReviewMUSH 4/19/2016 70
different spatial and temporal scales. Shall the high T geochemistry and1344
petrology community follow the low T geochemistry community and invest1345
timeindevelopingreactivetransportmodelingfortraceelementsandisotopes1346
inmagmabodies?The chemistry canbecomevery complicated, but the idea1347
eveninthecontextofoversimplifiedmodelsisworthpursuing.1348
• Tofocusoneruptiontriggeringmechanisms.Oneof the fundamentalsocietal1349
goalsinvolcanologyistounderstandthecauses(triggers)thatdrivevolcanic1350
eruptions.Thereareseveralpossible factors that can influence thestateofa1351
shallow reservoir and influence the timing of an eruption. Triggers can be1352
external (e.g. caused by a regional earthquakes, roof collapse, or magma1353
recharges from deeper; Sparks et al. 1977; Pallister et al. 1992;Watts et al.1354
1999; Eichelberger and Izbekov 2000; Gottsmann et al. 2009; Gregg et al.1355
2012) or internal (e.g. buoyancy, pressure buildup during recharge or gas1356
exsolution;e.g.,Caricchietal.2014;DegruyterandHuber2014;Malfaitetal.1357
2014).Fundamentally, thenotionof trigger,which isrelatedtoaneventora1358
process thathas a causal link to a subsequent eruption, remainsquite loose.1359
Establishing a causality between a trigger and an eruption is much more1360
challengingthanestablishingacorrelationbetweenthetwo.1361
• Tocontinueprovidingbettermodelsoflong-standingissuessuchasthe“room1362
problem”. Although the “room problem” is alleviated by having long-term1363
incrementaladditioninamainlyductilecrust,pushingmaterial(a)totheside,1364
(b) down, as dense cumulates from the lower crust founder back into the1365
mantle (Kay and Mahlburg Kay 1993; Jull and Kelemen 2001; Dufek and1366
ReviewMUSH 4/19/2016 71
Bergantz2005;JagoutzandSchmidt2013)and(c)upwards,asuppercrustal1367
reservoirdomeupduringresurgence(e.g.,SmithandBailey1968;Lipmanet1368
al. 1978; Marsh 1984; Hildreth 2004), the question continues to drive1369
controversies (e.g., Glazner and Bartley 2006; Clarke and Erdmann 2008;1370
GlaznerandBartley2008;Patersonetal.2008;YoshinobuandBarnes2008).1371
1372
7 Outlook 1373
At the present time, many questions remain to be answered about the migration,1374
emplacement, evolution and ultimately eruption of silicicmagmas in the upper crust. The1375
mainchallengesstemfromthefactthat:1376
(1) wehaveaccesstoonlyalimitedsetofindirectobservations,inmostcases1377
difficult to relate to the actual processes that control the chemical and1378
dynamicalevolutionofthesemagmasand1379
(2) mostmeltsgeneratedatdepthneverreachthesurface.1380
1381
Thedevelopmentofaself-consistentmodel forsilicicmagmasresiding intheupper1382
crust is complex and requires a joint effort across multiple disciplines. The mush model1383
presented in this review provides, we believe, a testable hypothesis from which better1384
models can be developed. In spite of what remains to be done to understand the fate of1385
magmasinthecrust,themushmodeloffersaself-consistentparadigmthatissupportedby1386
several independent observations from geophysics, geochemistry and petrology. For1387
instancethedevelopmentofmushzonesisconsistentwith1388
ReviewMUSH 4/19/2016 72
• Thermalmodelsofincrementally-growingmagmabodiesandgeophysicaldata1389
onactivesystemsrequirethatsuchreservoirsaredominantlycrystal-richon1390
long timescales (> 100 kys; Marsh 1981; Koyaguchi and Kaneko 1999;1391
BachmannandBergantz2004;CooperandKent2014).1392
• Chemical differentiation can occur internally by melt-crystal separation and1393
produce shorter-lived eruptible pockets (with melt content higher than 501394
vol%) from time to time.Melt extraction can largely occurwhen convection1395
currentswanesdown,i.e.whenmixingbystirringbecomeslessefficientthan1396
gravitational settling. Phase separation should be most efficient at1397
intermediate(40-70%)crystallinities.1398
• The combinationof incremental enthalpy additionsby recharges, latent heat1399
buffering and slower cooling rate of silicic magmas at high crystal content1400
reconciles the contrast between the longevity of magma centers/lifetime of1401
volcanicfields(asinferredfromzirconagepopulations)andthecomparatively1402
shortdurationoverwhichmagmasaremobileandpronetoerupt(Cooperand1403
Kent2014).1404
• Theanatomyofwell-exposedcross-sectionsinplutons(e.g.,Bachletal.2001;1405
Barnesetal.2001;Putirkaetal.2014)andthepresenceofplutoniclithologies1406
-cognateclastsinvolcanicunitswithcumulatesignature(Gelmanetal.2014;1407
Lee and Morton 2015; Wolff et al. 2015), although this aspect remains1408
controversial(e.g.,Glazneretal.2015;Kelleretal.2015).1409
1410
ReviewMUSH 4/19/2016 73
8 Acknowledgements 1411
Despite our attempt to cite the largest amount of previous work (we believe the1412
reference list is rather extensive with nearly 500 citations), we are certainly not giving1413
enoughduecredittotheamazingworkthatpeoplehavedoneovertheyearsinourtopicof1414
interest.Weapologize for this inadvance.Mostof these ideasput forwardherehavebeen1415
nucleatinginthewombofourownbiasedview.Wehavethemherefordiscussion,andtrust1416
our community that someormostof themwillbe challenged…We look forward to it.We1417
thankMikito Furuichi, NaomiMatthews,Marc-Antoine Longpré and Katy Chamberlain for1418
providing figures that we use to illustrate some recent advances in our field, and Keith1419
Putirkaformotivatingustowritethispaper.CommentsfromBenEllis,WimDegruyterand1420
PeterLipmanonapreviousversionof themanuscripthelpedbettercrystallizesomeideas1421
thatweretoountangledinamushydiscussion.WeareindebtedtoCharlieBaconandShan1422
deSilvaasformalreviewers,fortheinsightfulandconstructivecomments,aswellastothe1423
veryefficienteditorialhandlingbyFidelCosta.1424
9 References 1425
1426
Acocella,V.,DiLorenzo,R.,Newhall,C.,andScandone,R.(2015)Anoverviewofrecent(19881427to2014)calderaunrest:Knowledgeandperspectives.ReviewsofGeophysics,53(3),1428896-955.1429
Almeev, R.R., Bolte, T., Nash, B.P., Holtz, F.o., Erdmann, M., and Cathey, H.E. (2012) High-1430temperature, low-H2O SilicicMagmas of the YellowstoneHotspot: an Experimental1431Study of Rhyolite from the Bruneau-Jarbidge Eruptive Center, Central Snake River1432Plain,USA.JournalofPetrology,53(9),1837-1866.1433
Alonso-Perez, R., Müntener, O., and Ulmer, P. (2009) Igneous garnet and amphibole1434fractionationintherootsofislandarcs:experimentalconstraintsonandesiticliquids.1435ContributionstoMineralogyandPetrology,157(4),541-558.1436
Anderson,A.T.(1974)Chlorine,sulfurandwaterinmagmasandoceans.GeologicalSociety1437ofAmericaBulletin,85,1485-1492.1438
ReviewMUSH 4/19/2016 74
Anderson,A.T.,Davis,A.M.,andLu,F.(2000)EvolutionofBishopTuffrhyoliticmagmabased1439onmeltandmagnetiteinclusionsandzonedphenocrysts.JournalofPetrology,41(3),1440449-473.1441
Annen, C. (2009) From plutons to magma chambers: Thermal constraints on the1442accumulation of eruptible silicic magma in the upper crust. Earth and Planetary1443ScienceLetters,284(3-4),409-416.1444
Annen, C., Blundy, J.D., and Sparks, R.S.J. (2006) The genesis of intermediate and silicic1445magmasindeepcrustalhotzones.JournalofPetrology,47(3),505-539.1446
Annen,C.,Pichavant,M.,Bachmann,O.,andBurgisser,A.(2008)Conditionsforthegrowthof1447along-livedshallowcrustalmagmachamberbelowMountPeleevolcano(Martinique,1448LesserAntillesArc).JournalofGeophysicalResearch-SolidEarth,113(B7).1449
Annen,C.,andSparks,R.S.J. (2002)Effectsof repetitiveemplacementofbasaltic intrusions1450on thermal evolution andmelt generation in the crust. Earth andPlanetary Science1451Letters,203(3-4),937-955.1452
Arculus,R.J.,andWills,K.J.A.(1980)ThePetrologyofPlutonicBlocksandInclusionsfromthe1453LesserAntillesIslandArc.JournalofPetrology,21(4),743-799.1454
Bachl,C.A.,Miller,C.F.,Miller,J.S.,andFaulds,J.E.(2001)Constructionofapluton:Evidence1455fromanexposedcross-sectionoftheSearchlightpluton,EldoradoMountains,Nevada.1456GeologicalSocietyofAmericaBulletin,113,1213-1228.1457
Bachmann,O.(2010a)Thepetrologicevolutionandpre-eruptiveconditionsoftherhyolitic1458Kos Plateau Tuff (Aegean arc). Central European Journal of Geosciences, 2(3), 270-1459305.1460
Bachmann,O.(2010b)TimescalesAssociatedwithLargeSilicicMagmaBodies.InA.Dosseto,1461S.P.Turner,andJ.A.VanOrman,Eds.TimescalesofMagmaticProcesses:FromCoreto1462Atmosphere.Kluwer.1463
Bachmann,O., andBergantz,G.W. (2003)Rejuvenationof theFishCanyonmagmabody:A1464window into the evolution of large-volume silicic magma systems. Geology, 31(9),1465789-792.1466
Bachmann,O., andBergantz,G.W. (2004)On theoriginof crystal-poorrhyolites:Extracted1467frombatholithiccrystalmushes.JournalofPetrology,45(8),1565-1582.1468
Bachmann, O., and Bergantz, G.W. (2006) Gas percolation in upper-crustal silicic crystal1469mushesasamechanismforupwardheatadvectionandrejuvenationofnear-solidus1470magmabodies.JournalofVolcanologyandGeothermalResearch,149(1-2),85-102.1471
Bachmann, O., and Bergantz, G.W. (2008a) Deciphering Magma Chamber Dynamics from1472StylesofCompositionalZoning inLargeSilicicAshFlowSheets.Minerals, Inclusions1473andVolcanicProcesses,69,651-674.1474
Bachmann, O., and Bergantz, G.W. (2008b) Deciphering magma chamber dynamics from1475stylesofcompositionalzoninginlargesilicicashflowsheets.InK.D.Putirka,andF.J.1476Tepley,Eds.Minerals, inclusionsandvolcanicprocesses,69,p.651-674.Reviews in1477MineralogyandGeochemistryvol69.1478
Bachmann,O.,andBergantz,G.W.(2008c)RhyolitesandtheirSourceMushesacrossTectonic1479Settings.JournalofPetrology,49(12),2277-2285.1480
Bachmann, O., Charlier, B.L.A., and Lowenstern, J.B. (2007a) Zircon crystallization and1481recycling in the magma chamber of the rhyolitic Kos Plateau Tuff (Aegean Arc).1482Geology,35(1),73-76.1483
ReviewMUSH 4/19/2016 75
Bachmann,O.,Deering,C.,Lipman,P.,andPlummer,C.(2014)Buildingzonedignimbritesby1484recycling silicic cumulates: insight from the 1,000 km3 Carpenter Ridge Tuff, CO.1485ContributionstoMineralogyandPetrology,167(6),1-13.1486
Bachmann,O.,Deering,C.D.,Ruprecht, J.S.,Huber,C.,Skopelitis,A.,andSchnyder,C.(2012)1487EvolutionofsilicicmagmasintheKos-Nisyrosvolcaniccenter,Greece:apetrological1488cycle associated with caldera collapse. Contributions to Mineralogy and Petrology,1489163(1),151-166.1490
Bachmann,O., andDungan,M.A. (2002)Temperature-inducedAl-zoning inhornblendesof1491theFishCanyonmagma,Colorado.AmericanMIneralogist,87(8-9),1062-1076.1492
Bachmann,O.,Dungan,M.A.,andBussy,F.(2005)Insightsintoshallowmagmaticprocesses1493in large silicicmagma bodies: the trace element record in the Fish Canyonmagma1494body,Colorado.ContributionstoMineralogyandPetrology,149(3),338-349.1495
Bachmann, O., Dungan,M.A., and Lipman, P.W. (2002) The Fish Canyonmagma body, San1496Juanvolcanicfield,Colorado:Rejuvenationanderuptionofanupper-crustalbatholith.1497JournalofPetrology,43(8),1469-1503.1498
Bachmann,O.,Miller, C.F., andde Silva, S.L. (2007b)Thevolcanic-plutonic connection as a1499stage forunderstanding crustalmagmatism. JournalofVolcanologyandGeothermal1500Research,167(1-4),1-23.1501
Bachmann, O., Wallace, P.J., and Bourquin, J. (2010) The melt inclusion record from the1502rhyoliticKosPlateauTuff (AegeanArc). Contributions toMineralogyandPetrology,1503159(2),187-202.1504
Bacon, C.R., and Druitt, T.H. (1988a) Compositional evolution of the zoned calcalkaline1505magmachamberofMountMazama,CraterLake,Oregon.ContributionstoMineralogy1506andPetrology,98,224-256.1507
Bacon, C.R., and Druitt, T.H. (1988b) Compositional Evolution of the Zoned Calcalkaline1508MagmaChamberofMount-Mazama,CraterLake,Oregon.ContributionstoMineralogy1509andPetrology,98(2),224-256.1510
Bacon, C.R., and Lanphere, M.A. (2006) Eruptive history and geochronology of Mount1511MazamaandtheCraterLakeregion,Oregon.GSABulletin,118(11/12),1331–1359.1512
Bacon, C.R., and Lowenstern, J.B. (2005) Late Pleistocene granodiorite source for recycled1513zirconandphenocrystsinrhyodacitelavaatCraterLake,Oregon.EarthandPlanetary1514ScienceLetters,233(3-4),277-293.1515
Baker,D.R., andAlletti,M. (2012)Fluid saturation andvolatilepartitioningbetweenmelts1516and hydrous fluids in crustal magmatic systems: The contribution of experimental1517measurementsandsolubilitymodels.Earth-ScienceReviews,114(3-4),298-324.1518
Barboni,M.,Annen,C.,andSchoene,B.(2015)Evaluatingtheconstructionandevolutionof1519upper crustal magma reservoirs with coupled U/Pb zircon geochronology and1520thermalmodeling:AcasestudyfromtheMt.Capannepluton(Elba,Italy).Earthand1521PlanetaryScienceLetters.1522
Barker,S.J.,Wilson,C.J.N.,Smith,E.G.C.,Charlier,B.L.A.,Wooden,J.L.,Hiess,J.,andIreland,T.R.1523(2014) Post-supereruption Magmatic Reconstruction of Taupo Volcano (New1524Zealand),asReflectedinZirconAgesandTraceElements.JournalofPetrology,55(8),15251511-1533.1526
Barnes,C.G.,Burton,B.R.,Burling,T.C.,Wright,J.E.,andKarlsson,H.R.(2001)Petrologyand1527GeochemistryoftheLateEoceneHarrisonPassPluton,RubyMountainsCoreComplex,1528NortheasternNevada.JournalofPetrology,42(5),901-929.1529
ReviewMUSH 4/19/2016 76
Beane,R.,andWiebe,R.(2012)OriginofquartzclustersinVinalhavengraniteandporphyry,1530coastalMaine.ContributionstoMineralogyandPetrology,1-14.1531
Beard,J.S.,Ragland,P.C.,andCrawford,M.L.(2005)Reactivebulkassimilation:Amodelfor1532crust-mantlemixinginsilicicmagmas.Geology,33(8),681-684.1533
Bergantz,G.W.,andNi,J.(1999)Anumericalstudyofsedimentationbydrippinginstabilities1534inviscousfluids.InternationalJournalofMultiphaseFlow,25(2),307-320.1535
Bergantz,G.W.,Schleicher,J.M.,andBurgisser,A.(2015)Open-systemdynamicsandmixing1536inmagmamushes.NatureGeosci,8(10),793-796.1537
Berman, R.G. (1991) Thermobarometry using multi-equilibrium calculations: A new1538technique,withpetrologicalimplications.ContributionstoMineralogyandPetrology,153929,833-855.1540
Bindeman,I.,Schmitt,A.,andValley,J.(2006)U–Pbzircongeochronologyofsilicictuffsfrom1541theTimberMountain/OasisValleycalderacomplex,Nevada:rapidgenerationoflarge1542volume magmas by shallow-level remelting. Contributions to Mineralogy and1543Petrology,152(6),649-665.1544
Bindeman, I.N., and Valley, J.W. (2001) Low-18O rhyolites from Yellowstone: Magmatic1545evolutionbasedonzirconsandindividualphenocrysts.JournalofPetrology,42,1491-15461517.1547
Bindeman, I.N.,andValley, J.W. (2003)Rapidgenerationofbothhigh-and low-δ18O, large1548volumesilicicmagmasattheTimberMountain/OasisValleycalderacomplex,Nevada.1549GeologicalSocietyofAmericaBulletin,115(5),581-595.1550
Blake,S.,andCampbell, I.H.(1986)Thedynamicsofmagma-mixingduringflowinvolcanic1551conduits.ContributionstoMineralogyandPetrology,94(1),72-81.1552
Blake,S.,andIvey,G.N.(1986)Magmamixingandthedynamicsofwithdrawalfromstratified1553reservoirs.JournalofVolcanologyandGeothermalResearch,27(1-2),153-178.1554
Blundy,J.,andCashman,K.(2008)PetrologicReconstructionofMagmaticSystemVariables1555andProcesses.ReviewsinMineralogyandGeochemistry,69(1),179-239.1556
Blundy, J., Cashman,K.V.,Rust,A., andWitham,F. (2010)A case forCO2-richarcmagmas.1557EarthandPlanetaryScienceLetters,290(3-4),289-301.1558
Bohrson, W.A., and Spera, F.J. (2007) Energy-Constrained Recharge, Assimilation, and1559Fractional Crystallization (EC-RAFC): A Visual Basic computer code for calculating1560trace element and isotope variations of open-system magmatic systems. Geochem.1561Geophys.Geosyst.,8.1562
Bohrson,W.A., Spera, F.J., Ghiorso,M.S.,Brown,G.A., Creamer, J.B., andMayfield,A. (2014)1563Thermodynamic Model for Energy-Constrained Open-System Evolution of Crustal1564MagmaBodiesUndergoingSimultaneousRecharge,AssimilationandCrystallization:1565theMagmaChamberSimulator.JournalofPetrology,55(9),1685-1717.1566
Bonnefoi,C.C.,Provost,A.,andAlbarede,F.(1995)The'Dalygap'asamagmaticcatastrophe.1567Nature,378(6554),270-272.1568
Boroughs, S., Wolff, J.A., Ellis, B.S., Bonnichsen, B., and Larson, P.B. (2012) Evaluation of1569models for the origin of Miocene low-d18O rhyolites of the Yellowstone/Columbia1570RiverLargeIgneousProvince.EarthandPlanetaryScienceLetters,313-314(0),45-55.1571
Boudreau,A.E.(1999)PELE—aversionoftheMELTSsoftwareprogramforthePCplatform.1572Computers&Geosciences,25(2),201-203.1573
Bowen,N.L.(1928)Theevolutionofigneousrocks.332p.Doverpublications,NewYork.1574
ReviewMUSH 4/19/2016 77
Brandeis,G.,andJaupart,C.(1986)Ontheinteractionbetweenconvectionandcrystallization1575incoolingmagmachambers.EarthandPlanetaryScienceLetters,77(3-4),345-361.1576
Brandeis, G., and Marsh, B.D. (1990) Transient magmatic convection prolonged by1577solidification.GeophysicalresearchLetters,17(8),1125-1128.1578
Brenguier, F., Shapiro, N.M., Campillo, M., Ferrazzini, V., Duputel, Z., Coutant, O., and1579Nercessian, A. (2008) Towards forecasting volcanic eruptions using seismic noise.1580NatureGeoscience,1,126-130.1581
Brophy, J.G. (1991) Composition gaps, critical crystallinity, and fractional crystallization in1582orogenic (calc-alkaline) magmatic systems. Contributions to Mineralogy and1583Petrology,109(2),173-182.1584
Brown,S.J.A.,andFletcher,I.R.(1999)SHRIMPU-Pbdatingofthepreeruptiongrowthhistory1585ofzirconsfromthe340kaWhakamaruIgnimbrite,NewZealand:Evidencefor>2501586k.y.magmaresidencetimes.Geology,27(11),1035-1038.1587
Buddington, A.F. (1959) Granite emplacement with special reference to North America.1588GeologicalSocietyofAmericaBulletin,70,671-748.1589
Bunsen,R. (1851)Ueberdieprozesseder vulkanishenGesteinsbildungen Islands.Annalen1590derPhysics(Leipzig),83,197-272.1591
Burgisser,A.,andBergantz,G.W.(2011)Arapidmechanismtoremobilizeandhomogenize1592highlycrystallinemagmabodies.Nature,471(7337),212-215.1593
Burgisser, A., and Scaillet, B. (2007) Redox evolution of a degassing magma rising to the1594surface.Nature,194-197.1595
Burton,M.,Allard,P.,Muré,F., andLaSpina,A. (2007)MagmaticGasCompositionReveals1596theSourceDepthofSlug-DrivenStrombolianExplosiveActivity.Science,317(5835),1597227-230.1598
Candela, P.A. (1997)A reviewof shallow, ore-related granites: Textures, volatiles, andore1599metals.JournalofPetrology,38(12),1619-1633.1600
Cardoso,S.S.S.,andWoods,A.W.(1999)Onconvectioninavolatile-saturatedmagma.Earth1601andPlanetaryScienceLetters,168,301-310.1602
Caricchi,L.,Annen,C.,Blundy,J.,Simpson,G.,andPinel,V.(2014)Frequencyandmagnitude1603of volcanic eruptions controlled by magma injection and buoyancy. Nature Geosci,1604advanceonlinepublication.1605
Caricchi, L., and Blundy, J. (2015) Experimental petrology of monotonous intermediate1606magmas.GeologicalSociety,London,SpecialPublications,422.1607
Caricchi,L.,Burlini,L.,Ulmer,P.,Gerya,T.,Vassali,M.,andPapale,P.(2007)Non-Newtonian1608rheology of crystal-bearing magmas and implications for magma ascent dynamics.1609EarthandPlanetaryScienceLetters,264,402-419.1610
Cashman, K.V., and Giordano, D. (2014) Calderas and magma reservoirs. Journal of1611VolcanologyandGeothermalResearch,288,28-45.1612
Cashman, K.V., and Sparks, R.S.J. (2013) How volcanoes work: A 25 year perspective.1613GeologicalSocietyofAmericaBulletin.1614
Chamberlain, K.J., Morgan, D.J., and Wilson, C.J.N. (2014a) Timescales of mixing and1615mobilisation in the Bishop Tuff magma body: perspectives from diffusion1616chronometry.ContributionstoMineralogyandPetrology,168(1),1-24.1617
Chamberlain,K.J.,Wilson,C.J.N.,Wooden,J.L.,Charlier,B.L.A.,andIreland,T.R.(2014b)New1618Perspectives on the Bishop Tuff from Zircon Textures, Ages and Trace Elements.1619JournalofPetrology,55(2),395-426.1620
ReviewMUSH 4/19/2016 78
Champallier,R.,Bystricky,M., andArbaret,L. (2008)Experimental investigationofmagma1621rheology at 300 MPa: From pure hydrous melt to 76 vol.% of crystals. Earth and1622PlanetaryScienceLetters,267(3-4),571-583.1623
Charlier, B., Namur, O., Toplis, M.J., Schiano, P., Cluzel, N., Higgins, M.D., and Auwera, J.V.1624(2011) Large-scale silicate liquid immiscibility during differentiation of tholeiitic1625basalttograniteandtheoriginoftheDalygap.Geology,39(10),907-910.1626
Charlier,B.L.A.,Bachmann,O.,Davidson,J.P.,Dungan,M.A.,andMorgan,D.(2007)TheUpper1627CrustalEvolutionofaLargeSilicicMagmaBody:Evidence fromCrystal-ScaleRb/Sr1628Isotopic Heterogeneities in the Fish CanyonMagmatic System, Colorado. Journal of1629Petrology,48(10),1875-1894.1630
Charlier, B.L.A., Peate, D.W., Wilson, C.J.N., Lowenstern, J.B., Storey, M., and Brown, S.J.A.1631(2003) Crystallisation ages in coeval silicic magma bodies: 238U-230Th1632disequilibrium evidence from the Rotoiti and Earthquake Flat eruption deposits,1633Taupo Volcanic Zone, New Zealand. Earth and Planetary Science Letters, 206(3-4),1634441-457.1635
Charlier,B.L.A.,Wilson,C.J.N.,Lowenstern, J.B.,Blake,S.,VanCalsteren,P.W.,andDavidson,1636J.P. (2005) Magma Generation at a Large, Hyperactive Silicic Volcano (Taupo, New1637Zealand) Revealed by U–Th and U–Pb Systematics in Zircons. Journal of Petrology,163846(1),3-32.1639
Chayes, F. (1963) Relative Abundance of Intermediate Members of the Oceanic Basalt-1640TrachyteAssociation.Journalofgeophysicalresearch,68,1519-1534.1641
Chiaradia, M. (2014) Copper enrichment in arc magmas controlled by overriding plate1642thickness.NatureGeosci,7(1),43-46.1643
Christiansen,R.L.(2001)TheQuaternaryandPlioceneYellowstonePlateauVolcanicFieldof1644Wyoming,Idaho,andMontana.U.S.GeologicalSurveyProfessionalPaper,729-G,145.1645
Cimarelli,C.,Costa,A.,Mueller,S.,andMader,H.M.(2011)Rheologyofmagmaswithbimodal1646crystalsizeandshapedistributions:Insightsfromanalogexperiments.Geochemistry,1647Geophysics,Geosystems,12(7),n/a-n/a.1648
Civetta, L.,Orsi, G., Pappalardo, L., Fisher,R.V.,Heiken,G., andOrt,M. (1997)Geochemical1649zoning, mingling, eruptive dynamics and depositional processes-the Campanian1650Ignimbrite,CampiFlegrei,Italy.JournalofVolcanologyandGeothermalResearch,75,1651183-219.1652
Claiborne, L.L., Miller, C.F., Flanagan, D.M., Clynne, M.A., and Wooden, J.L. (2010) Zircon1653revealsprotractedmagmastorageandrecyclingbeneathMountSt.Helens.Geology,165438(11),1011-1014.1655
Clarke, D.B., and Erdmann, S. (2008) Is stoping a volumetrically significant pluton1656emplacement process?: Comment. Geological Society of America Bulletin, 120(7-8),16571072-1074.1658
Coint,N.,Barnes,C.G.,Yoshinobu,A.S.,Barnes,M.A.,andBuck,S.(2013)Useoftraceelement1659abundancesinaugiteandhornblendetodeterminethesize,connectivity,timing,and1660evolutionofmagmabatchesinatiltedbatholith.Geosphere,9(6),1747-1765.1661
Coleman,D.S.,Gray,W.,andGlazner,A.F.(2004)Rethinkingtheemplacementandevolution1662ofzonedplutons;geochronologicevidenceforincrementalassemblyoftheTuolumne1663IntrusiveSuite,California.Geology,32,433-436.1664
Connolly, J.A.D. (2009) The geodynamic equation of state: What and how. Geochemistry,1665Geophysics,Geosystems,10(10),n/a-n/a.1666
ReviewMUSH 4/19/2016 79
Cooper,K.M.,andKent,A.J.R.(2014)Rapidremobilizationofmagmaticcrystalskeptincold1667storage.Nature,506(7489),480-483.1668
Cooper,K.M.,andReid,M.R.(2003)Re-examinationofcrystalagesinrecentMountSt.Helens1669lavas: implications for magma reservoir processes. Earth and Planetary Science1670Letters,213(1-2),149-167.1671
Cordonnier, B., Caricchi, L., Pistone, M., Castro, J., Hess, K.-U., Gottschaller, S., Manga, M.,1672Dingwell,D.B.,andBurlini,L.(2012)Theviscous-brittletransitionofcrystal-bearing1673silicicmelt:Direct observation ofmagma rupture andhealing. Geology, 40(7), 611-1674614.1675
Costa, A., Caricchi, L., and Bagdassarov, N. (2009) A model for the rheology of particle-1676bearing suspensions and partially molten rocks. Geochemistry, Geophysics,1677Geosystems,10(3),n/a-n/a.1678
Costa,F.(2008)ResidenceTimesofSilicicMagmasAssociatedwithCalderas.InJ.Gottsmann,1679andJ.MartÌ,Eds.DevelopmentsinVolcanology,10,p.1-55.Elsevier,Amsterdam.1680
Costa,F.,Scaillet,B.,andGourgaud,A.(2003)MassiveatmosphericsulfurloadingoftheAD16811600 Huaynaputina eruption and implications for petrologic sulfur estimates.1682Geophys.Res.Lett.,30(2).1683
Costa,F.,Scaillet,B.,andPichavant,M.(2004)Petrologicalandexperimentalconstraintson1684thepre-eruptionconditionsofHolocenedacitefromVolcanSanPedro(36degreesS,1685ChileanAndes)and the importanceofsulphur insilicicsubduction-relatedmagmas.1686JournalofPetrology,45(4),855-881.1687
Couch,S.,Sparks,R.S.J.,andCarroll,M.R.(2001)Mineraldisequilibriuminlavasexplainedby1688convectiveself-mixinginopenmagmachambers.Nature,411,1037-1039.1689
Crisp,J.A.(1984)Ratesofmagmaemplacementandvolcanicoutput.JournalofVolcanology1690andGeothermalResearch,20,177-211.1691
Daly,R.A.(1914)Igneousrocksandtheirorigin.563p.McGraw-Hill,London.1692Daly,R.A.(1925)ThegeologyofAscensionIsland.ProceedingsoftheAmericanAcademyof1693
ArtsandSciences,60,1-80.1694Daly,R.A.(1933)IgneousrocksandthedepthsoftheEarth.McGrawHill,NewYork.1695Davaille,A.,andJaupart,C.(1993)Transienthigh-Rayleighnumberthermalconvectionwith1696
largeviscosityvariations.JournalofFluidMechanics,253,141-166.1697Dawson,P.B.,Evans,J.R.,andIyer,H.M.(1990)Teleseismictomographyofthecompressional1698
wave velocity structure beneath the Long Valley region. Journal of geophysical1699research,95(B7),11021-11050.1700
De Natale, G., Troise, C., Trigila, R., Dolfi, D., and Chiarabba, C. (2004) Seismicity and 3-D1701substructureatSomma-Vesuviusvolcano:evidenceformagmaquenching.Earthand1702PlanetaryScienceLetters,221(1-4),181-196.1703
deSilva,S.L.(1991)StylesofzoninginthecentralAndeanignimbrites:Insightsintomagma1704chamber processes. InHarmon, R.S., Rapela, C.W (eds): Andeanmagmatism and its1705tectonicsetting,GeologicalSocietyofAmericaSpecialPaper,265,233-243.1706
deSilva,S.L.,andGosnold,W.(2007a)CordilleranBatholithdevelopment: insights froman1707ignimbriteflare-up.JournalofVolcanologyandGeothermalResearch.1708
deSilva, S.L., andGosnold,W.D. (2007b)Episodic constructionofbatholiths: Insights from1709thespatiotemporaldevelopmentofanignimbriteflare-up.JournalofVolcanologyand1710GeothermalResearch,167(1–4),320-335.1711
ReviewMUSH 4/19/2016 80
de Silva, S.L., and Gregg, P.M. (2014) Thermomechanical feedbacks in magmatic systems:1712Implications for growth, longevity, and evolution of large caldera-forming magma1713reservoirsandtheirsupereruptions.JournalofVolcanologyandGeothermalResearch,1714282(0),77-91.1715
deSilva,S.L.,Self,S.,Francis,P.W.,Drake,R.E.,andCarlosRamirez,R.(1994)Effusivesilicic1716volcanism in the Central Andes: The Chao dacite and other young lavas of the1717Altiplano-Puna Volcanic Complex. Journal of geophysical research, 99(B9), 17805-171817825.1719
de Silva, S.L., and Wolff, J.A. (1995) Zoned magma chambers; the influence of magma1720chamber geometryon sidewall convective fractionation. Journal ofVolcanology and1721GeothermalResearch,65(1-2),111-118.1722
deSilva,S.L.,Zandt,G.,Trumbull,R.,andViramonte,J.(2006)Largescalesilicicvolcanism-1723the result of thermal maturation of the crust. In Y.-t. Chen, Ed. Advances in1724Geosciences,1,p.215-230.WorldScientificPress.1725
Deering,C.D.,andBachmann,O.(2010)Traceelementindicatorsofcrystalaccumulationin1726silicicigneousrocks.EarthandPlanetaryScienceLetters,297(1-2),324-331.1727
Deering,C.D.,Bachmann,O.,Dufek,J.,andGravley,D.M.(2011a)Rift-RelatedTransitionFrom1728AndesitetoRhyoliteVolcanismintheTaupoVolcanicZone(NewZealand)controlled1729byCrystal-MeltDynamicsinMushZonesWithVariableMineralAssemblages.Journal1730ofPetrology,52(11),2243-2263.1731
Deering, C.D., Bachmann,O., andVogel, T.A. (2011b)TheAmmoniaTanksTuff: Erupting a1732melt-rich rhyolite cap and its remobilized crystal cumulate. Earth and Planetary1733ScienceLetters,310(3-4),518-525.1734
Deering, C.D., Keller, B., Schoene, B., Bachmann, O., Beane, R., and Ovtcharova, M. (2016)1735Zircon record of the plutonic-volcanic connection and protracted rhyolite melt1736evolution.Geology.1737
Degruyter,W.,andHuber,C.(2014)Amodelforeruptionfrequencyofuppercrustalsilicic1738magmachambers.EarthandPlanetaryScienceLetters,403(0),117-130.1739
Degruyter, W., Huber, C., Bachmann, O., Cooper, K.M., and Kent, A.J.R. (2015) Magma1740reservoir response to transient recharge events: The case of Santorini volcano1741(Greece).Geology.1742
DelGaudio,P.,Ventura,G.,andTaddeucci,J.(2013)Theeffectofparticlesizeontherheology1743of liquid-solid mixtures with application to lava flows: Results from analogue1744experiments.Geochemistry,Geophysics,Geosystems,14(8),2661-2669.1745
DePaolo, D.J. (1981) Trace element and isotopic effects of combinedwallrock assimilation1746andfractionalcrystallization.EarthandPlanetaryScienceLetters,53(2),189-202.1747
Dorais, M.J., Whitney, J.A., and Stormer, J.C. (1991) Mineralogical constraints on the1748petrogenesisof trachytic inclusions,CarpenterRidgeTuff,CentralSan Juanvolcanic1749field,Colorado.ContributionstoMineralogyandPetrology,107(2),219-230.1750
Drenth,B.J.,andKeller,G.R.(2004)NewgravityandmagneticmapsoftheSanJuanvolcanic1751field, southwestern colorado. EOS Transaction, American Geophysical Union,175285(F623).1753
Drenth, B.J., Keller, G.R., and Thompson, R.A. (2012) Geophysical study of the San Juan1754Mountainsbatholithcomplex,southwesternColorado.Geosphere,8(3),669-684.1755
ReviewMUSH 4/19/2016 81
Druitt,T.H.,andBacon,C.R.(1989)PetrologyoftheZonedCalcalkalineMagmaChamberof1756Mount Mazama, Crater Lake, Oregon. Contributions to Mineralogy and Petrology,1757101(2),245-259.1758
Druitt, T.H., Costa, F., Deloule, E., Dungan, M., and Scaillet, B. (2012) Decadal to monthly1759timescales of magma transfer and reservoir growth at a caldera volcano. Nature,1760482(7383),77-80.1761
Ducea,M.,andSaleeby,J.B.(1998)Crustalrecyclingbeneathcontinentalarcs;silica-richglass1762inclusions in ultramafic xenoliths from the Sierra Nevada, California. Earth and1763PlanetaryScienceLetters,156(1-2),101-116.1764
Dufek, J., and Bachmann, O. (2010) Quantum magmatism: Magmatic compositional gaps1765generatedbymelt-crystaldynamics.Geology,38(8),687-690.1766
Dufek, J., and Bergantz, G.W. (2005) Lower Crustal Magma Genesis and Preservation: a1767Stochastic Framework for the Evaluation of Basalt–Crust Interaction. Journal of1768Petrology,46,2167-2195.1769
Dunbar,N.W.,Campbell,A.R.,andCandela,P.A.(1996)Physical,chemical,andmineralogical1770evidence formagmatic fluidmigrationwithin theCapitanpluton, southeasternNew1771Mexico.GeologicalSocietyofAmericaBulletin,108(3),318-333.1772
Dunbar, N.W., Kyle, P.R., andWilson, C.J.N. (1989) Evidence for limited zonation in silicic1773magmasystems,Taupovolcaniczone,NewZealand.Geology,17(3),234-236.1774
Dungan, M.A., Long, P.E., and Rhodes, J.M. (1978) Magma mixing at mid-ocean ridges:1775Evidencefromlegs45and46DSDP.Geophys.Res.Lett.,5(6),423-425.1776
Edmonds,M.,Oppenheimer,C.,Pyle,D.M.,Herd,R.A.,andThompson,G.(2003)SO2emissions1777from Soufriere Hills Volcano and their relationship to conduit permeability,1778hydrothermal interaction and degassing regime. Journal of Volcanology and1779GeothermalResearch,124(1-2),23-43.1780
Eichelberger,J.C.(1975)Originofandesiteanddacite;evidenceofmixingatGlassMountain1781inCaliforniaandatotherCircum-Pacificvolcanoes.GeolSocAmBull,86(10),1381-17821391.1783
Eichelberger, J.C., Chertkoff, D.G., Dreher, S.T., and Nye, C.J. (2000) Magmas in collision;1784rethinkingchemicalzonationinsilicicmagmas.Geology,28(7),603-606.1785
Eichelberger,J.C.,andIzbekov,P.E.(2000)Eruptionofandesitetriggeredbydykeinjection;1786contrasting cases at Karymsky Volcano, Kamchatka and Mt Katmai, Alaska.1787Philosophical Transactions - Royal Society. Mathematical, Physical and Engineering1788Sciences,358(1770),1465-1485.1789
Eiler, J., Stolper, E.M., andMcCanta,M.C. (2011) Intra- and IntercrystallineOxygen Isotope1790VariationsinMineralsfromBasaltsandPeridotites.JournalofPetrology.1791
Eiler, J.M., Crawford, A., Elliott, T.I.M., Farley, K.A., Valley, J.W., and Stolper, E.M. (2000)1792OxygenIsotopeGeochemistryofOceanic-ArcLavas.J.Petrology,41(2),229-256.1793
Ellis,B.S.,Bachmann,O.,andWolff,J.A.(2014)Cumulatefragmentsinsilicicignimbrites:The1794caseoftheSnakeRiverPlain.Geology,42(5),431-434.1795
Ellis,B.S.,andWolff,J.A.(2012)ComplexstorageofrhyoliteinthecentralSnakeRiverPlain.1796JournalofVolcanologyandGeothermalResearch,211-212,1-11.1797
Ellis, B.S., Wolff, J.A., Boroughs, S., Mark, D.F., Starkel, W.A., and Bonnichsen, B. (2013)1798RhyoliticvolcanismofthecentralSnakeRiverPlain:areview.BullVolcanol75,745.1799
Evans,B.W.,andBachmann,O.(2013)Implicationsofequilibriumanddisequilibriumamong1800crystalphasesintheBishopTuff.AmericanMineralogist,98(1),271-274.1801
ReviewMUSH 4/19/2016 82
Evans, B.W., Hildreth, E., Bachmann, O., and Scaillet, B. (2016) In defense of Magnetite-1802IlmeniteThermometry in theBishopTuff and its implication for gradients in silicic1803magmareservoirs.AmericanMIneralogist,101(2),469-482.1804
Ewart,A.(1982)ThemineralogyandpetrologyofTertiary-Recentorogenicvolcanicrocks:1805withspecialreferencetotheandesitic-basalticcompositionalrange.InR.S.Thorpe,Ed.1806Andesites:OrogenicAndesitesandRelatedRocks,p.25-95.JohnWiley,NewYork.1807
Faroughi, S.A., andHuber,C. (2015)Unifying the relativehinderedvelocity in suspensions1808and emulsions of nondeformable particles. Geophysical research Letters, 42(1),18092014GL062570.1810
Farrell,J.,Smith,R.B.,Husen,S.,andDiehl,T.(2014)Tomographyfrom26 yearsofseismicity1811revealingthatthespatialextentoftheYellowstonecrustalmagmareservoirextends1812well beyond the Yellowstone caldera. Geophysical research Letters, 41(9),18132014GL059588.1814
Fiege,A.,Behrens,H.,Holtz,F.o.,andAdams,F.(2014)Kineticvs.thermodynamiccontrolof1815degassingofH2O-S±Cl-bearing andesiticmelts. Geochimica et CosmochimicaActa,1816125,241-264.1817
Fiege,A.,Holtz,F.o.,Behrens,H.,Mandeville,C.W.,Shimizu,N.,Crede,L.S.,andGöttlicher,1818J.r. (2015) Experimental investigation of the S and S-isotope distribution between1819H2O–S ± Cl fluids and basaltic melts during decompression. Chemical Geology,1820393–394,36-54.1821
Folkes, C.B., de Silva, S.L., Schmitt, A.K., and Cas, R.A.F. (2011a) A reconnaissance of U-Pb1822zirconagesintheCerroGalánsystem,NWArgentina:Prolongedmagmaresidence,1823crystal recycling, and crustal assimilation. Journal of Volcanology and Geothermal1824Research,206(3–4),136-147.1825
Folkes,C.B.,deSilva,S.L.,Wright,H.M.,andCas,R.A.F.(2011b)Geochemicalhomogeneityofa1826long-lived,largesilicicsystem;evidencefromtheCerroGaláncaldera,NWArgentina.1827BulletinofVolcanology.1828
Folkes,C.B., Silva,S.L.,Wright,H.M., andCas,R.A.F. (2011c)Geochemicalhomogeneityofa1829long-lived,largesilicicsystem;evidencefromtheCerroGaláncaldera,NWArgentina.1830BulletinofVolcanology,73(10),1455-1486.1831
Forni,F.,Ellis,B.S.,Bachmann,O.,Lucchi,F.,Tranne,C.A.,Agostini, S., andDallai,L. (2015)1832EruptedcumulatefragmentsinrhyolitesfromLipari(AeolianIslands).Contributions1833toMineralogyandPetrology,170(5),1-18.1834
Fournier,T.J.,Pritchard,M.E.,andRiddick,S.N.(2010)Duration,magnitude,andfrequencyof1835subaerial volcanodeformationevents:Newresults fromLatinAmericausing InSAR1836andaglobalsynthesis.Geochemistry,Geophysics,Geosystems,11(1),n/a-n/a.1837
Francalanci,L.,Varekamp, J.C.,Vougioukalakis,G.,Defant,M.J., Innocenti,F.,andManetti,P.1838(1995) Crystal retention, fractionation and crustal assimilation in a convecting1839magmachamber,NisyrosVolcano,Greece.BulletinofVolcanology,56(8),601-620.1840
Francis,P.W.,Sparks,R.S.J.,Hawkesworth,C.J.,Thorpe,R.S.,Pyle,D.M.,Tait,S.R.,Mantovani,1841M.S.,andMcDermott,F.(1989)PetrologyandgeochemistryoftheCerroGalancaldera,1842northwestArgentina.GeologicalMagazine,126(5),515-547.1843
Freundt-Malecha,B.,Schmicke,H.-U.,andFreundt,A.(2001)Plutonicrocksofintermediate1844compositions on Gran Canaria: the missing link of the bimodal volcanic suite.1845ContributionstoMineralogyandPetrology,141,430-445.1846
ReviewMUSH 4/19/2016 83
Friedman, I., Lipman, P.W., Obradovich, J.D., Gleason, J.D., and Christiansen, R.L. (1974)1847MeteoricWaterinMagmas.Science,184,1069-1072.1848
Furuichi, M., and Nishiura, D. (2014) Robust coupled fluid-particle simulation scheme in1849Stokes-flow regime: Toward the geodynamic simulation including granular media.1850Geochemistry,Geophysics,Geosystems,15(7),2865-2882.1851
Gardner, J., Befus, K., Gualda, G.R., and Ghiorso, M. (2014) Experimental constraints on1852rhyolite-MELTSand theLateBishopTuffmagmabody.Contributions toMineralogy1853andPetrology,168(2),1-14.1854
Gebauer,S.,Schmitt,A.,Pappalardo,L.,Stockli,D.,andLovera,O.(2014)Crystallizationand1855eruptionagesofBrecciaMuseo(CampiFlegreicaldera,Italy)plutonicclastsandtheir1856relation to the Campanian ignimbrite. Contributions to Mineralogy and Petrology,1857167(1),1-18.1858
Geist,D.,Howard,K.A.,andLarson,P.(1995)TheGenerationofOceanicRhyolitesbyCrystal1859Fractionation: the Basalt-Rhyolite Association at Volcan Alcedo, Galapagos1860Archipelago.J.Petrology,36(4),965-982.1861
Gelman,S.E.,Deering,C.D.,Bachmann,O.,Huber,C.,andGutierrez,F.J.(2014)Identifyingthe1862crystalgraveyardsremainingafterlargesiliciceruptions.EarthandPlanetaryScience1863Letters,403(0),299-306.1864
Gelman,S.E.,Deering,C.D.,Gutierrez,F.J.,andBachmann,O.(2013a)EvolutionoftheTaupo1865VolcanicCenter,NewZealand:petrologicalandthermalconstraints fromtheOmega1866dacite.ContributionstoMineralogyandPetrology,166(5),1355-1374.1867
Gelman,S.E.,Gutierrez,F.J.,andBachmann,O.(2013b)Onthelongevityoflargeuppercrustal1868silicicmagmareservoirs.Geology,41(7),759-762.1869
Gerlach,T.M.,Westrich,H.R.,andSymonds,R.B.(1996)Preeruptionvapor inmagmaofthe1870climacticMount Pinatubo eruption: Source of the giant stratospheric sulfur dioxide1871cloud.InC.Newhall,andR.S.Punongbayan,Eds.FireandMud:EruptionsandLahars1872ofMountPinatubo,Philipinnes.UniversityofWashingtonPress,Seattle.1873
Ghiorso,M.S., and Sack, R.O. (1995a) Chemicalmass transfer inmagmatic processes IV: A1874revised and internally consistent thermodynamic model for the interpolation and1875extrapolationofliquid-solidequilibriainmagmaticsystemsatelevatedtemperatures1876andpressures.ContributionstoMineralogyandPetrology,119,197-212.1877
Ghiorso,M.S., and Sack, R.O. (1995b) ChemicalMass-Transfer inMagmatic Processes .4. A1878Revised and Internally Consistent ThermodynamicModel for the Interpolation and1879Extrapolation of Liquid-Solid Equilibria in Magmatic Systems at Elevated-1880Temperatures and Pressures. Contributions toMineralogy and Petrology, 119(2-3),1881197-212.1882
Gibert, D., Beauducel, F., Declais, Y., Lesparre,N.,Marteau, J., Nicollin, F., andTarantola, A.1883(2010)Muontomography:PlansforobservationsintheLesserAntilles.Earth,Planets1884andSpace,62(2),153-165.1885
Giggenbach,W.F.(1996)Chemicalcompositionofvolcanicgases.InR.Scarpa,andR.I.Tilling,1886Eds.MonitoringandMitigationofVolcanicHazards,p.221–256,.Springer,Berlin.1887
Glazner, A., Coleman, D., and Mills, R. (2015) The Volcanic-Plutonic Connection, p. 1-22.1888SpringerBerlinHeidelberg.1889
Glazner, A.F., and Bartley, J.M. (2006) Is stoping a volumetrically significant pluton1890emplacementprocess?GeologicalSocietyofAmericaBulletin,118(9-10),1185-1195.1891
ReviewMUSH 4/19/2016 84
Glazner, A.F., and Bartley, J.M. (2008) Reply to comments on "Is stoping a volumetrically1892significant pluton emplacement process?". Geological Society of America Bulletin,1893120(7-8),1082-1087.1894
Glazner,A.F.,Coleman,D.S.,andBartley,J.M.(2008)Thetenuousconnectionbetweenhigh-1895silicarhyolitesandgranodioriteplutons.Geology,36(2).1896
Goff,F.,Janik,C.J.,Delgado,H.,Werner,C.,Counce,D.,Stimac,J.A.,Siebe,C.,Love,S.P.,Williams,1897S.N., Fischer, T.P., and Johnson, L. (1998) Geochemical surveillance of magmatic1898volatiles at Popocatepetl Volcano, Mexico. Geological Society of America Bulletin,1899110(6),695-710.1900
Gonnermann, H.M., and Manga, M. (2007) The fluid mechanics inside a volcano. Annual1901ReviewsofFluidMechanics,39,321-356.1902
Gonnermann,H.M.,andManga,M.(2013)Dynamicsofmagmaascentinthevolcanicconduit.1903InModelingVolcanicProcesses,p.55-84.CambridgeUniversityPress.1904
Gottsmann, J.,Lavallee,Y.,Marti, J.,andAguirre-Diaz,G. (2009)Magma-tectonic interaction1905and theeruptionof silicicbatholiths.EarthandPlanetaryScienceLetters,284(3-4),1906426-434.1907
Graeter,K.,Beane,R.J.,Deering,C.D.,Gravley,D.M.,andBachmann,O.(inpress)Formationof1908rhyoliteattheOkatainaVolcanicComplex,NewZealand:Newinsightsfromanalysis1909ofquartzclustersinplutoniclithics.AmericanMineralogist,100.1910
Graeter,K.A., Beane,R.J.,Deering, C.D., Gravley,D., andBachmann,O. (2015)Formationof1911rhyoliteattheOkatainaVolcanicComplex,NewZealand:Newinsightsfromanalysis1912ofquartzclustersinplutoniclithics.AmericanMIneralogist,100(8-9),1778-1789.1913
Graham, I.J., Cole, J.W., Briggs, R.M., Gamble, J.A., and Smith, I.E.M. (1995) Petrology and1914petrogenesis of volcanic rocks from the Taupo Volcanic Zone: a review. Journal of1915VolcanologyandGeothermalResearch,68,59-87.1916
Greene, A.R., Debari, S.M., Kelemen, P.B., Blusztajn, J., and Clift, P.D. (2006) A Detailed1917Geochemical Study of Island Arc Crust: the Talkeetna Arc Section, South-Central1918Alaska.J.Petrology,47(6),1051-1093.1919
Gregg, P.M., de Silva, S.L., and Grosfils, E.B. (2013) Thermomechanics of shallow magma1920chamberpressurization:Implicationsfortheassessmentofgrounddeformationdata1921atactivevolcanoes.EarthandPlanetaryScienceLetters,384,100-108.1922
Gregg, P.M., de Silva, S.L., Grosfils, E.B., and Parmigiani, J.P. (2012) Catastrophic caldera-1923forming eruptions: Thermomechanics and implications for eruption triggering and1924maximum caldera dimensions on Earth. Journal of Volcanology and Geothermal1925Research,241–242(0),1-12.1926
Grove,T.L.,andDonnelly-Nolan,J.M.(1986)TheevolutionofyoungsiliciclavasatMedicine1927Lake Volcano, California: Implications for the origin of compositional gaps in calc-1928alkalineserieslavas.ContributionstoMineralogyandPetrology,92,281-302.1929
Grove, T.L.,Donnelly-Nolan, J.M., andHoush,T. (1997)Magmatic processes that generated1930therhyoliteofGlassMountain,MedicineLakevolcano,N.California.Contributionsto1931MineralogyandPetrology,127(3),205-223.1932
Grunder,A.L.,Klemetti,E.W.,Feeley,T.C.,andMcKee,C.L.(2008)Elevenmillionyearsofarc1933volcanismattheAucanquilchaVolcanicCluster,northernChileanAndes:Implications1934for the lifespanandemplacementofbatholiths.Transactionsof theRoyalSocietyof1935Edinburgh:EarthSciences,97(4),415–436.1936
ReviewMUSH 4/19/2016 85
Gualda,G.A.R.,andGhiorso,M.S.(2013a)TheBishopTuffgiantmagmabody:analternative1937totheStandardModel.ContributionstoMineralogyandPetrology,166(3),755-775.1938
Gualda, G.A.R., and Ghiorso, M.S. (2013b) Low-pressure origin of high-silica rhyolites and1939granites.TheJournalofGeology,121(5),537-545.1940
Gualda, G.A.R., Ghiorso, M.S., Lemons, R.V., and Carley, T.L. (2012) Rhyolite-MELTS: A1941modified calibration of MELTS optimized for silica-rich, fluid-bearing magmatic1942systems.JournalofPetrology,53(5),875-890.1943
Guillong,M.,vonQuadt,A.,Sakata,S.,Peytcheva,I.,andBachmann,O.(2014)LA-ICP-MSPb-U1944datingofyoungzirconsfromtheKos-Nisyrosvolcaniccentre,SEAegeanarc.Journal1945ofAnalyticalAtomicSpectrometry,29(6),963-970.1946
Gutierrez, F., and Parada, M.A. (2010) Numerical Modeling of Time-dependent Fluid1947Dynamics and Differentiation of a Shallow Basaltic Magma Chamber. Journal of1948Petrology,51(3),731-762.1949
Gutierrez, F., Payacan, I., Gelman, S.E., Bachmann, O., and Parada, M.A. (2013) Late-stage1950magma flow in a shallow felsic reservoir: Merging the anisotropy of magnetic1951susceptibility record with numerical simulations in La Gloria Pluton, central Chile.1952JournalofGeophysicalResearch-SolidEarth,118(5),1984-1998.1953
Halliday,A.N.,Davidson,J.P.,Hildreth,W.,andHolden,P.(1991)Modelingthepetrogenesisof1954highRb/Srsilicicmagmas.ChemicalGeology,92,107-114.1955
Halliday, A.N., Fallick, A.E., Hutchinson, J., and Hildreth, W. (1984) A Nd, Sr, O isotopic1956investigation into the causes of chemical and isotopic zonation in the Bishop Tuff,1957California.EarthandPlanetaryScienceLetters,68,378-391.1958
Hamilton, W., and Myers, W.B. (1967) The nature of batholiths. U.S. Geological Survey1959ProfessionalPaper,554-C,30p.1960
Hautmann, S., Witham, F., Christoper, T., Cole, P., Linde, A.T., Sacks, S., and Sparks, R.S.J.1961(2014)StrainfieldanalysisonMontserrat(W.I.)astoolforassessingpermeableflow1962paths in themagmatic systemof SoufrièreHillsVolcano.Geochemistry,Geophysics,1963Geosystems,15.1964
Heinrich, C.A., and Candela, P.A. (2012) Fluids and Ore Formation in the Earth’s Crust.1965TreatiseonGeochemistry,ed.2,13,1-28.1966
Heise,W., Caldwell, T.G., Bibby, H.M., and Bennie, S.L. (2010) Three-dimensional electrical1967resistivity imageofmagmabeneath an active continental rift, TaupoVolcanic Zone,1968NewZealand.Geophys.Res.Lett.,37(10),L10301.1969
Heliker, C. (1995) Inclusions inMount St.Helensdacite erupted from1980 through1983.1970JournalofVolcanologyandGeothermalResearch,66(1-4),115-135.1971
Hildreth,W.(1979)TheBishopTuff:evidencefortheoriginofthecompositionalzonationin1972silicicmagmachambers.InC.E.Chapin,andW.E.Elston,Eds.Ash-FlowTuffs,180,p.197343-76.GeologicalSocietyofAmerica,SpecialPaper180.1974
Hildreth, W. (1981) Gradients in silicic magma chambers: Implications for lithospheric1975magmatism.Journalofgeophysicalresearch,86(B11),10153-10192.1976
Hildreth,W.,andFierstein,J.(2000)Katmaivolcanicclusterandthegreateruptionof1912.1977GeologicalSocietyofAmericaBulletin,112(10),1594-1620.1978
Hildreth, W., Halliday, A.N., and Christiansen, R.L. (1991) Isotopic and chemical evidence1979concerning the genesis and contamination of basaltic and rhyoliticmagma beneath1980theYellowstonePlateauvolcanicfield.JournalofPetrology,32(1),63-137.1981
ReviewMUSH 4/19/2016 86
Hildreth,W.S. (2004)VolcanologicalperspectivesonLongValley,MammothMountain,and1982Mono Craters: several contiguous but discrete systems. Journal of Volcanology and1983GeothermalResearch,136(3-4),169-198.1984
Hildreth,W.S. (2007)QuaternaryMagmatism in theCascades-GeologicalPerspectives.U.S.1985GeologicalSurveyProfessionalPaper,1744,125pages.1986
Hildreth,W.S.,andWilson,C.J.N.(2007)CompositionalZoningintheBishopTuff.Journalof1987Petrology,48(5),951-999.1988
Hill, G.J., Caldwell, T.G., Chertkoff, D.G., Bibby, H.M., Burgess,M.K., Cull, J.P., and Cas, R.A.F.1989(2009)DistributionofmeltbeneathMountStHelensandMountAdamsinferredfrom1990magnetotelluricdata.NatureGeoscience,2,785-789.1991
Holland, T.J.B., and Powell, R. (2011) An improved and extended internally consistent1992thermodynamicdatasetforphasesofpetrological interest, involvinganewequation1993ofstateforsolids.JournalofMetamorphicGeology,29(3),333-383.1994
Holtzman,R.,Szulczewski,M.L.,andJuanes,R.(2012)CapillaryFracturinginGranularMedia.1995PhysicalReviewLetters,108(26),264504.1996
Hooper, A., Zebker, H., Segall, P., and Kampes, B. (2004) A new method for measuring1997deformation on volcanoes and other natural terrains using InSAR persistent1998scatterers.GeophysicalresearchLetters,31(23),n/a-n/a.1999
Huang, F., Chakraborty, P., Lundstrom, C.C., Holmden, C., Glessner, J.J.G., Kieffer, S.W., and2000Lesher,C.E.(2010)Isotopefractionationinsilicatemeltsbythermaldiffusion.Nature,2001464(7287),396-400.2002
Huang, H.-H., Lin, F.-C., Schmandt, B., Farrell, J., Smith, R.B., and Tsai, V.C. (2015) The2003Yellowstone magmatic system from the mantle plume to the upper crust. Science,2004348(6236),773-776.2005
Huber,C.,Bachmann,O.,andDufek,J.(2010a)Thelimitationsofmeltingonthereactivation2006ofsilicicmushes.JournalofVolcanologyandGeothermalResearch,195(2-4),97-105.2007
Huber, C., Bachmann, O., and Dufek, J. (2011) Thermo-mechanical reactivation of locked2008crystal mushes: Melting-induced internal fracturing and assimilation processes in2009magmas.EarthandPlanetaryScienceLetters,304(3-4),443-454.2010
Huber,C.,Bachmann,O.,andDufek,J.(2012a)Crystal-poorversuscrystal-richignimbrites:A2011competitionbetweenstirringandreactivation.Geology,40(2),115-118.2012
Huber,C.,Bachmann,O.,andManga,M.(2009)Homogenizationprocesses insilicicmagma2013chambersby stirring andmushification (latent heat buffering). Earth andPlanetary2014ScienceLetters,283(1-4),38-47.2015
Huber,C.,Bachmann,O.,andManga,M.(2010b)TwoCompetingEffectsofVolatilesonHeat2016Transfer in Crystal-rich Magmas: Thermal Insulation vs Defrosting. Journal of2017Petrology,51(4),847-867.2018
Huber, C., Bachmann, O., Vigneresse, J.L., Dufek, J., and Parmigiani, A. (2012b) A physical2019modelformetalextractionandtransportinshallowmagmaticsystems.Geochemistry2020GeophysicsGeosystems,13,Q08003,doi:10.1029/2012GC004042.2021
Huber,C.,Parmigiani,A.,Latt,J.,andDufek,J.(2013)Channelizationofbuoyantnonwetting2022fluidsinsaturatedporousmedia.WaterResourcesResearch,49(10),6371-6380.2023
Hughes,G.R.,andMahood,G.A.(2008)Tectoniccontrolsonthenatureoflargesiliciccalderas2024involcanicarcs.Geology,36(8),627-630.2025
ReviewMUSH 4/19/2016 87
Humphreys,M.C.S.,Edmonds,M.,Christopher,T.,andHards,V.(2009)Chlorinevariationsin2026themagmaofSoufriereHillsVolcano,Montserrat:InsightsfromClinhornblendeand2027meltinclusions.GeochimicaetCosmochimicaActa,73(19),5693-5708.2028
Huppert, H.E., Sparks, R.S.J., and Turner, J.S. (1982) Effects of volatiles onmixing in calc-2029alkalinemagmasystems.Nature,332,554-557.2030
Huppert,H.E., andWoods,A.W. (2002)The role of volatiles inmagma chamberdynamics.2031Nature,420(6915),493-495.2032
Husen,S.,Smith,R.B.,andWaite,G.P.(2004)Evidenceforgasandmagmaticsourcesbeneath2033the Yellowstone volcanic field from seismic tomographic imaging. Journal of2034VolcanologyandGeothermalResearch,131(3-4),397-410.2035
Irvine, T.N., Andersen, J.C.ø., and Brooks, C.K. (1998) Included blocks (and blocks within2036blocks) in the Skaergaard intrusion: Geologic relations and the origins of rhythmic2037modallygradedlayers.GeologicalSocietyofAmericaBulletin,110(11),1398-1447.2038
Ishibashi, H., and Sato, H. (2007) Viscosity measurements of subliquidus magmas: Alkali2039olivine basalt from the Higashi-Matsuura district, Southwest Japan. Journal of2040VolcanologyandGeothermalResearch,160(3–4),223-238.2041
Jagoutz, O., and Schmidt, M.W. (2012) The formation and bulk composition of modern2042juvenilecontinentalcrust:TheKohistanarc.ChemicalGeology,298-299(0),79-96.2043
Jagoutz,O.,andSchmidt,M.W.(2013)Thecompositionofthefounderedcomplementtothe2044continental crust and a re-evaluation of fluxes in arcs. Earth and Planetary Science2045Letters,371–372,177-190.2046
Jahns, R.H., and Tuttle, O.F. (1963) Layered pegmatites-aplites intrusives. Mineralogical2047SocietyofAmericaSpecialPaper,1,78-92.2048
Jaupart, C., and Brandeis, G. (1986) The stagnant bottom layer of convecting magma2049chambers.EarthandPlanetaryScienceLetters,80(1-2),183-199.2050
Jaupart,C.,Brandeis,G.,andAlegre,C.J. (1984)Stagnant layersatthebottomofconvecting2051magmachambers.Nature,308(5959),535-538.2052
Jay,J.,Pritchard,M.,West,M.,Christensen,D.,Haney,M.,Minaya,E.,Sunagua,M.,McNutt,S.,2053and Zabala, M. (2012) Shallow seismicity, triggered seismicity, and ambient noise2054tomographyat the long-dormantUturuncuVolcano,Bolivia.BulletinofVolcanology,205574(4),817-837.2056
Jellinek, A.M., and DePaolo, D.J. (2003) A model for the origin of large silicic magma2057chambers:precursorsofcaldera-formingeruptions.BulletinofVolcanology,65,363-2058381.2059
Jellinek, A.M., and Kerr, R.C. (1999) Mixing and compositional stratification produced by2060naturalconvection:2.Applicationstothedifferentiationofbasalticandsilicicmagma2061chambersandkomatiite lava flows. Journalofgeophysical research,104(B4),7203-20627218.2063
Johannes,W.,andHoltz,F.(1996)Petrogenesisandexperimentalpetrologyofgraniticrocks.2064335p.Springer-Verlag,Berlin.2065
Johnson,M., and Rutherford, M. (1989) Experimentally determined conditions in the Fish2066CanyonTuff,Colorado,magmachamber.JournalofPetrology,30,711-737.2067
Jull,M.,andKelemen,P.B.(2001)Ontheconditionsforlowercrustalconvectiveinstability.2068Journalofgeophysicalresearch,106,6423-6446.2069
ReviewMUSH 4/19/2016 88
Kamiyama, H., Nakajima, T., Kamioka, H. (2007) Magmatic Stratigraphy of the Tilted2070TottabetsuPlutonicComplex,Hokkaido,NorthJapan:magmaChamberDynamicsand2071PlutonConstruction.JournalofGeology,115,295-314.2072
Karakas,O., andDufek, J. (2015)Meltevolutionandresidence inextendingcrust:Thermal2073modeling of the crust and crustal magmas. Earth and Planetary Science Letters,2074425(0),131-144.2075
Karlstrom,L.,Rudolph,M.L.,andManga,M.(2012)Calderasizemodulatedbytheyieldstress2076withinacrystal-richmagmareservoir.NatureGeosci,5(6),402-405.2077
Kay, R.W., and Mahlburg Kay, S. (1993) Delamination and delamination magmatism.2078Tectonophysics,219,177-89.2079
Keller, C.B., and Schoene, B. (2012) Statistical geochemistry reveals disruption in secular2080lithosphericevolutionabout2.5[thinsp]Gyrago.Nature,485(7399),490-493.2081
Keller, C.B., Schoene, B., Barboni, M., Samperton, K.M., and Husson, J.M. (2015) Volcanic-2082plutonic parity and the differentiation of the continental crust. Nature, 523(7560),2083301-307.2084
Keller,J.(1969)Originofrhyolitesbyanatecticmeltingofgraniticcrustalrocks;theexample2085of rhyolitic pumice from the island of Kos (Aegean sea). Bulletin Volcanologique,208633(3),942-959.2087
Kennedy,B.M.,MarkJellinek,A.,andStix,J.(2008)Coupledcalderasubsidenceandstirring2088inferredfromanaloguemodels.NatureGeosci,1(6),385-389.2089
Klemetti,E.,andGrunder,A.(2008)VolcanicevolutionofVolcánAucanquilcha:along-lived2090dacitevolcanointheCentralAndesofnorthernChile.BulletinofVolcanology,70(5),2091633-650.2092
Klemetti,E.W.,andClynne,M.A.e.(2014)LocalizedRejuvenationofaCrystalMushRecorded2093in Zircon Temporal and Compositional Variation at the Lassen Volcanic Center,2094NorthernCalifornia.PLoSONE,9(12),e113157.2095
Klemetti,E.W.,Deering,C.D.,Cooper,K.M.,andRoeske,S.M.(2011)Magmaticperturbations2096intheOkatainaVolcanicComplex,NewZealandatthousand-yeartimescalesrecorded2097insinglezirconcrystals.EarthandPlanetaryScienceLetters,305(1–2),185-194.2098
Koyaguchi,T.,andBlake,S.(1989)Thedynamicsofmagmamixinginarisingmagmabatch.2099BulletinofVolcanology,52(2),127-137.2100
Koyaguchi,T.,Hallworth,M.A.,andHuppert,H.E.(1993)Anexperimentalstudyontheeffects2101of phenocrysts on convection in magmas. Journal of Volcanology and Geothermal2102Research,55(1-2),15-32.2103
Koyaguchi, T., Hallworth, M.A., Huppert, H.E., and Sparks, R.S.J. (1990) Sedimentation of2104particlesfromaconvectingfluid.Nature,343(6257),447-450.2105
Koyaguchi, T., and Kaneko, K. (1999) A two-stage thermal evolutionmodel of magmas in2106continentalcrust.JournalofPetrology,40(2),241-254.2107
Lagios,E.,Sakkas,V.,Parcharidis, I.,andDietrich,V.(2005)GrounddeformationofNisyros2108Volcano (Greece) for the period 1995-2002: Results from DInSAR and DGPS2109observations.BulletinofVolcanology,68(2),201-214.2110
Laumonier,M.,Scaillet,B.,Pichavant,M.,Champallier,R.m.,Andujar,J.,andArbaret,L.(2014)2111On the conditions of magmamixing and its bearing on andesite production in the2112crust.NatCommun,5.2113
Lavallée, Y., Hess, K.-U., Cordonnier, B., and Bruce Dingwell, D. (2007) Non-Newtonian2114rheologicallawforhighlycrystallinedomelavas.Geology,35(9),843-846.2115
ReviewMUSH 4/19/2016 89
Lee, C.-T.A., and Morton, D.M. (2015) High silica granites: Terminal porosity and crystal2116settlinginshallowmagmachambers.EarthandPlanetaryScienceLetters,409(0),23-211731.2118
Lee,C.-T.A.,Morton,D.M.,Farner,M.J.,andMoitra,P.(2015)Fieldandmodelconstraintson2119silicicmelt segregation by compaction/hindered settling: The role of water and its2120effectonlatentheatrelease.AmericanMIneralogist,100(8-9),1762-1777.2121
Leeman, W.P., Annen, C., and Dufek, J. (2008) Snake River Plain – Yellowstone silicic2122volcanism: implications for magma genesis and magma fluxes. In C. Annen, and G.2123Zellmer,Eds.DynamicsofCrustalMagmaTransfer,StorageandDifferentiation,304,p.2124235-259.GeologicalSociety,London.2125
Lees,J.M.(1992)ThemagmasystemofMountSt.Helens:non-linearhigh-resolutionP-wave2126tomography.JournalofVolcanologyandGeothermalResearch,53(1-4),103-116.2127
Lees, J.M. (2007) Seismic tomography of magmatic systems. Journal of Volcanology and2128GeothermalResearch,167(1-4),37-56.2129
Lejeune, A.-M., and Richet, P. (1995) Rheology of crystal-bearing silicate melts; an2130experimentalstudyathighviscosities.Journalofgeophysicalresearch,100(3),4215-21314229.2132
Lindsay, J.M., Schmitt, A.K., Trumbull, R.B., De Silva, S.L., Siebel, W., and Emmermann, R.2133(2001) Magmatic evolution of the La Pacana caldera system, Central Andes, Chile:2134Compositionalvariationof twocogenetic, large-volume felsic ignimbrites. Journalof2135Petrology,42(3),459-486.2136
Lipman, P.W. (1967) Mineral and chemical variations within an ash-flow sheet from Aso2137caldera, SouthWestern Japan. Contributions toMineralogy and Petrology, 16, 300-2138327.2139
Lipman,P.W.(1984)Therootsofash-flowcalderasinwesternNorthAmerica:windowsinto2140thetopsofgraniticbatholiths.JournalofGeophysicalResearch,89(B10),8801-8841.2141
Lipman,P.W. (2000)ThecentralSan Juancalderacluster:Regionalvolcanic framework. in2142P.M. Bethke and R.L. Hay, eds., Ancient Lake Creede: Its Volcano-Tectonic Setting,2143HistoryofSedimentation,andRelationofMineralizationintheCreedeMiningDistrict:2144GeologicalSocietyofAmericaSpecialPaper,346,9-69.2145
Lipman,P.W.(2006)ChemicalAnalysesOfTertiaryVolcanicRocks,CentralSanJuanCaldera2146Complex,SouthwesternColorado,Open-FileReport2004-1194.2147
Lipman, P.W. (2007) Incremental assembly and prolonged consolidation of Cordilleran2148magma chambers: Evidence from the Southern Rocky Mountain Volcanic Field.2149Geosphere,3(1),1-29.2150
Lipman,P.W., andBachmann,O. (2015) Ignimbrites tobatholiths: Integratingperspectives2151fromgeological,geophysical,andgeochronologicaldata.Geosphere,11(3).2152
Lipman,P.W.,Doe,B.,andHedge,C.(1978)PetrologicevolutionoftheSanJuanvolcanicfield,2153Southwestern Colorado: Pb and Sr isotope evidence. Geological Society of America2154Bulletin,89,59-82.2155
Lipman,P.W.,Dungan,M.A.,andBachmann,O.(1997)Comagmaticgranophyricgraniteinthe2156Fish Canyon Tuff, Colorado: Implications for magma-chamber processes during a2157largeash-floweruption.Geology,25(10),915-918.2158
Lipman, P.W., Dungan, M.A., Brown, L.L., and Deino, A.L. (1996) Recurrent eruption and2159subsidence at the Platoro Caldera complex, southeastern San Juan volcanic field,2160
ReviewMUSH 4/19/2016 90
Colorado; new tales from old tuffs. Geological Society of America Bulletin, 108(8),21611039-1055.2162
Lipman, P.W., andMcIntosh,W.C. (2008) Eruptive andnoneruptive calderas, northeastern2163San Juan Mountains, Colorado: Where did the ignimbrites come from? Geological2164SocietyofAmericaBulletin,120(7-8),771-795.2165
Lohmar, S., Parada, M., Gutierrez, F., Robin, C., and Gerbe, M.C. (2012) Mineralogical and2166numerical approaches to establish the pre-eruptive conditions of the mafic Lican2167Ignimbrite,VillarricaVolcano (ChileanSouthernAndes). JournalofVolcanologyand2168GeothermalResearch,235-236(0),55-69.2169
Lowenstern,J.B.(2003)Meltinclusionscomeofage:Volatiles,Volcanoes,andSorby'sLegacy.2170In B. De Vivo, and R.J. Bodnar, Eds. Melt Inclusions in Volcanic Systems: Methods,2171ApplicationsandProblems.,Developments inVolcanology5,p.1-22.ElsevierPress,2172Amsterdam.2173
Lowenstern, J.B., and Hurvitz, S. (2008) Monitoring a Supervolcano in Repose: Heat and2174VolatileFluxattheYellowstoneCaldera.Elements,4,35-40.2175
Lowenstern,J.B.,Persing,H.M.,Wooden,J.L.,Lanphere,M.,Donnelly-Nolan,J.,andGrove,T.L.2176(2000) U-Th dating of single zircons from young granitoid xenoliths: new tools for2177understandingvolcanicprocesses.EarthandPlanetaryScienceLetters,183(1-2),291-2178302.2179
Luhr, J.F., Carmichael, I.S.E., and Varekamp, J.C. (1984) The 1982 eruptions of El ChichÛn2180Volcano,Chiapas,Mexico:Mineralogyandpetrologyoftheanhydritebearingpumices.2181JournalofVolcanologyandGeothermalResearch,23(1-2),69-108.2182
Lukács,R.,Harangi,S.,Bachmann,O.,Guillong,M.,Danišík,M.,vonQuadt,A.,Dunkl,I.,Fodor,2183L., Sliwinski, J., Soós, I., and Szepesi, J. (in press) Zircon geochronology and2184geochemistrytoconstraintheyoungesteruptioneventsandmagmaevolutionofthe2185Mid-Miocene ignimbrite flare-up in the Pannonian basin, eastern-central Europe.2186ContributionstoMineralogyandPetrology.2187
Lyell,C.S.(1838)Elementsofgeology,JohnMurray,London.2188Macdonald,R.,Belkin,H.E.,Fitton,J.G.,Rogers,N.W.,Nejbert,K.,Tindle,A.G.,andMarshall,A.S.2189
(2008) The Roles of Fractional Crystallization, Magma Mixing, Crystal Mush2190Remobilization and Volatile-Melt Interactions in the Genesis of a Young Basalt-2191PeralkalineRhyoliteSuite,theGreaterOlkariaVolcanicComplex,KenyaRiftValley.J.2192Petrology,49(8),1515-1547.2193
Mader,H.M.,Llewellin,E.W.,andMueller,S.P.(2013)Therheologyoftwo-phasemagmas:A2194reviewandanalysis.JournalofVolcanologyandGeothermalResearch,257,135-158.2195
Malfait,W.J.,Seifert,R.,Petitgirard,S.,Perrillat,J.-P.,Mezouar,M.,Ota,T.,Nakamura,E.,Lerch,2196P.,andSanchez-Valle,C. (2014)Supervolcanoeruptionsdrivenbymeltbuoyancy in2197largesilicicmagmachambers.NatureGeosci,7,122-125.2198
Marsh,B.D.(1981)Onthecrystallinity,probabilityofoccurrence,andrheologyof lavaand2199magma.ContributionstoMineralogyandPetrology,78,85-98.2200
Marsh,B.D. (1984)On theMechanicsofCalderaResurgence.1984,CalderasandAssociate2201IgneousRocks,p.8245-8251.AmericanGeophysicalUnion.2202
Marsh,B.D. (1989a)Magmachambers.AnnualReviewofEarthandPlanetarySciences,17,2203439-474.2204
Marsh,B.D.(1989b)Onconvectivestyleandvigorinsheet-likemagmachambers.Journalof2205Petrology,30(3),479-530.2206
ReviewMUSH 4/19/2016 91
Marsh, B.D. (1996) Solidification fronts and magmatic evolution. Mineralogical Magazine,220760(1),5-40.2208
Marsh, B.D. (2002) On bimodal differentiation by solidification front instability in basaltic2209magmas, part 1: basicmechanics. Geochimica et Cosmochimica Acta, 66(12), 2211-22102229.2211
Marsh, B.D., and Maxey, M.R. (1985) On the distribution and separation of crystals in2212convectingmagma.JournalofVolcanologyandGeothermalResearch,24,95-150.2213
Marteau, J., Gibert, D., Lesparre, N., Nicollin, F., Noli, P., and Giacoppo, F. (2012) Muons2214tomography applied to geosciences and volcanology. Nuclear Instruments and2215Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and2216AssociatedEquipment,695,23-28.2217
Martin,D., andNokes,R. (1988)Crystal settling invigorously convectingmagmachamber.2218Nature,332(7),534-536.2219
Martin, D., and Nokes, R. (1989) A fluid-dynamical study of crystal settling in convecting2220magmas.JournalofPetrology,30(6),1471-1500.2221
Martin, V.M., Morgan, D.J., Jerram, D.A., Caddick, M.J., Prior, D.J., and Davidson, J.P. (2008)2222Bang! Month-Scale Eruption Triggering at Santorini Volcano. Science, 321(5893),22231178.2224
Mason, B.G., Pyle,D.M., andOppenheimer, C. (2004)The size and frequency of the largest2225explosiveeruptionsonEarth.BulletinofVolcanology,66,735-748.2226
Massonnet, D., Briole, P., and Arnaud, A. (1995) Deflation of Mount Etna monitored by2227spaceborneradar interferometry.Nature,375(6532),567-570.2228
Masturyono, McCaffrey, R., Wark, D.A., and Roecker, S.W. (2001) Distribution of magma2229beneath theToba caldera complex,northSumatra, Indonesia, constrainedby three-2230dimensionalPwavevelocities,seismicity,andgravitydata.Geochemistry,Geophysics,2231Geosystems,2.2232
Matsuo,S. (1962)Establishmentofchemicalequilibrium in thevolcanicgasobtained from2233thelavalakeofKilauea,Hawaii.BulletinVolcanologique,24(1),59-71.2234
Matthews,N., Pyle, D., Smith, V.,Wilson, C., Huber, C., and vanHinsberg, V. (2012)Quartz2235zoningand thepre-eruptive evolutionof the~340-kaWhakamarumagma systems,2236NewZealand.ContributionstoMineralogyandPetrology,163(1),87-107.2237
Matzel, J.E.P., Bowring, S.A., and Miller, R.B. (2006) Time scales of pluton construction at2238differing crustal levels: Examples from the Mount Stuart and Tenpeak intrusions,2239North Cascades, Washington. Geological Society of America Bulletin, 118(11/12),22401412-1430.2241
Maughan,L.L.,Christiansen,E.H.,Best,M.G.,Gromme,C.S.,Deino,A.L.,andTingey,D.G.(2002)2242The Oligocene Lund Tuff, Great Basin, USA: a very large volume monotonous2243intermediate.JournalofVolcanologyandGeothermalResearch,113,129-157.2244
McBirney, A.R. (1980) Mixing and unmixing of magmas. Journal of Volcanology and2245GeothermalResearch,7,357-371.2246
McBirney,A.R.(1993)IgneousPetrology.508p.JonesandBarlett,London.2247McBirney,A.R.(1995)MechanismsofDifferentiationintheSkaergaardIntrusion.Journalof2248
theGeologicalSociety,152,421-435.2249McBirney, A.R., Baker, B.H., and Nilson, R.H. (1985) Liquid fractionation. Part 1: Basic2250
principles and experimental simulations. Journal of Volcanology and Geothermal2251Research,24,1-24.2252
ReviewMUSH 4/19/2016 92
McCarthy, T.S., and Groves, D.I. (1979) The Blue Tier Batholith, Northeastern Tasmania.2253ContributionstoMineralogyandPetrology,71(2),193-209.2254
McKenzie, D.P. (1985) The extraction of magma from the crust and mantle. Earth and2255PlanetaryScienceLetters,74,81-91.2256
Melekhova, E., Annen, C., and Blundy, J. (2013) Compositional gaps in igneous rock suites2257controlledbymagmasystemheatandwatercontent.NatureGeosci,6(5),385-390.2258
Metrich,N.,andMandeville,C.W.(2010)Sulfurinmagmas.Elements,6,81-86.2259Michaut,C.,andJaupart,C.(2006)Ultra-rapidformationoflargevolumesofevolvedmagma.2260
EarthandPlanetaryScienceLetters,250(1-2),38-52.2261Miller, C.F., and Miller, J.S. (2002) Contrasting stratified plutons exposed in tilt blocks,2262
EldoradoMountains,ColoradoRiverRift,NV,USA.Lithos,61,209-224.2263Miller, C.F., and Wark, D.A. (2008) Supervolcanoes and their explosive supereruptions.2264
Elements,4,11-16.2265Miller,J.S.,Matzel,J.E.P.,Miller,C.F.,Burgess,S.D.,andMiller,R.B.(2007)Zircongrowthand2266
recyclingduringtheassemblyoflarge,compositearcplutons.JournalofVolcanology2267andGeothermalResearch,167(1-4),282-299.2268
Mills, J.G., Saltoun, B.W., and Vogel, T.A. (1997) Magma batches in the timber mountain2269magmatic system, southwestern Nevada volcanic field, Nevada, USA. Journal of2270VolcanologyandGeothermalResearch,78(3-4),185-208.2271
Mohamed, F.H. (1998) Geochemistry and petrogenesis of El Gezira ring complex, Egypt: a2272monzosyenite cumulate derived from fractional crystallization of trachyandesitic2273magma.JournalofVolcanologyandGeothermalResearch,84(1-2),103-123.2274
Moitra, P., and Gonnermann, H.M. (2015) Effects of crystal shape- and size-modality on2275magmarheology.Geochemistry,Geophysics,Geosystems,16(1),1-26.2276
Molloy,C.,Shane,P.,andNairn,I.(2008)Pre-eruptionthermalrejuvenationandstirringofa2277partly crystalline rhyolite pluton revealed by the Earthquake Flat Pyroclastics2278deposits,NewZealand.JournaloftheGeologicalSociety,London,,165,435-447.2279
Morgan, D.J., and Blake, S. (2006) Magmatic residence times of zoned phenocrysts:2280introduction and application of the binary element diffusion modelling (BEDM)2281technique.ContributionstoMineralogyandPetrology,151(1),58-70.2282
Morse,S.A.(2011)Thefractionallatentheatofcrystallizingmagmas.AmericanMineralogist,228396,682-689.2284
Mueller,S.,Llewellin,E.W.,andMader,H.M.(2011)Theeffectofparticleshapeonsuspension2285viscosityand implications formagmatic flows.GeophysicalresearchLetters,38(13),2286n/a-n/a.2287
Muntener, O., and Ulmer, P. (2006) Experimentally derived high-pressure cumulates from2288hydrousarcmagmasandconsequencesfortheseismicvelocitystructureoflowerarc2289crust.GeophysicalResearchLetters,33,doi:10.1029/2006GL027629.2290
Murphy,M.D.,Sparks,R.S.J.,Barclay,J.,Carroll,M.R.,andBrewer,T.S.(2000)Remobilization2291of andesitic magma by intrusion of mafic magma at the Soufrière Hills Volcano,2292Montserrat,WestIndies.JournalofPetrology,41(1),21-42.2293
Namiki, A., Hatakeyama, T., Toramaru, A., Kurita, K., and Sumita, I. (2003) Bubble size2294distributionsinaconvectinglayer.Geophysicalresearchletters,30,2-4.2295
Nash, B.P., Perkins, M.E., Christensen, J.N., Lee, D.-C., and Halliday, A.N. (2006) The2296Yellowstonehotspot in spaceand time:NdandHf isotopes in silicicmagmas.Earth2297andPlanetaryScienceLetters,247(1-2),143-156.2298
ReviewMUSH 4/19/2016 93
Newman, A.V., Dixon, T.H., and Gourmelen, N. (2006) A four-dimensional viscoelastic2299deformation model for Long Valley Caldera, California, between 1995 and 2000.2300JournalofVolcanologyandGeothermalResearch,150(1–3),244-269.2301
Nilson, R.H., McBirney, A.R., and Baker, B.H. (1985) Liquid fractionation. Part 2: Fluid2302dynamicsandquantitativeimplicationsformagmaticsystems.JournalofVolcanology2303andGeothermalResearch,24(25-54).2304
Nishimura, K. (2009) A trace-element geochemical model for imperfect fractional2305crystallization associated with the development of crystal zoning. Geochimica et2306CosmochimicaActa,73(7),2142-2149.2307
Oldenburg, C.M., Spera, F.J., Yuen, D.A., and Sewell, G. (1989) Dynamic mixing in magma2308bodies:Theory,simulations,andimplications.Journalofgeophysicalresearch,94(B7),23099215-9236.2310
Oppenheimer,J.,Rust,A.C.,Cashman,K.V.,andSandnes,B.(2015)Gasmigrationregimesand2311outgassinginparticle-richsuspensions.FrontiersinPhysics,3.2312
Orsi, G., de Vita, S., and Di Vito, M. (1996) The restless, resurgent Campi Flegrei nested2313caldera(Italy):constraintsonitsevolutionandconfiguration.JournalofVolcanology2314andGeothermalResearch,74,179-214.2315
Otamendi, J.E., Ducea, M.N., and Bergantz, G.W. (2012) Geological, Petrological and2316GeochemicalEvidence forProgressiveConstructionofanArcCrustalSection,Sierra2317deValleFertil,FamatinianArc,Argentina.JournalofPetrology,53(4),761-800.2318
Pallister, J.S.,Hoblitt,R.P.,andReyes,A.G.(1992)Abasalttriggerforthe1991eruptionsof2319Pinatubovolcano?Nature,356,426-428.2320
Pappalardo, L., and Mastrolorenzo, G. (2012) Rapid differentiation in a sill-like magma2321reservoir:acasestudyfromthecampiflegreicaldera.Sci.Rep.,2.2322
Parmigiani, A., Faroughi, S.A., Huber, C., Bachmann, O., and Su, Y. (In press) Bubble2323accumulationanditsroleontheevolutionofuppercrustalmagmareservoirs.Nature.2324
Parmigiani,A.,Huber,C.,andBachmann,O.(2014)Mushmicrophysicsandthereactivation2325ofcrystal-richmagmareservoirs.JournalofGeophysicalResearch:SolidEarth,119(8),23266308-6322.2327
Parmigiani,A.,Huber,C.,Bachmann,O.,andChopard,B.(2011)Pore-scalemassandreactant2328transportinmultiphaseporousmediaflows.JournalofFluidMechanics,686,40-76.2329
Paterson,S.R.,Pignotta,G.S.,Farris,D.,Memeti,V.,Miller,R.B.,Vernon,R.H.,and≈Ω√°k,J.ô.2330(2008) Is stoping a volumetrically significant pluton emplacement process?:2331Discussion.GeologicalSocietyofAmericaBulletin,120(7-8),1075-1079.2332
Paulatto,M.,Minshull, T.A., Baptie, B.,Dean, S.,Hammond, J.O.S.,Henstock, T., Kenedi, C.L.,2333Kiddle,E.J.,Malin,P.,Peirce,C.,Ryan,G.,Shalev,E.,Sparks,R.S.J.,andVoight,B.(2010)2334Upper crustal structureof anactivevolcano fromrefraction/reflection tomography,2335Montserrat,LesserAntilles.GeophysicalJournalInternational,180(2),685-696.2336
Pe-Piper,G.,andMoulton,B.(2008)MagmaevolutioninthePliocene-Pleistocenesuccession2337ofKos,SouthAegeanarc(Greece).Lithos,106(1-2),110-124.2338
Peccerillo, A., Barberio, M.R., Yirgu, G., Ayalew, D., Barbieri, M., and Wu, T.W. (2003)2339Relationships between Mafic and Peralkaline Silicic Magmatism in Continental Rift2340Settings: a Petrological, Geochemical and Isotopic Study of the Gedemsa Volcano,2341CentralEthiopianRift.J.Petrology,44(11),2003-2032.2342
Petford,N.(2009)Whicheffectiveviscosity?MineralogicalMagazine,73(2),167-191.2343
ReviewMUSH 4/19/2016 94
Petford, N., Atherton, M.P., and Halliday, A.N. (1996) Rapid magma production rates,2344underplating and remelting in the Andes: isotopic evidence from northern-central2345Peru(9-11°S).JournalofSouthAmericanEarthSciences,9,69-78.2346
Petford, N., Cruden, A.R., McCaffrey, K.J.W., and Vigneresse, J.-L. (2000) Granite magma2347formation,transportandemplacementintheEarth'scrust.Nature,408,669-673.2348
Phillips, J.C., and Woods, A.W. (2002) Suppression of large-scale magma mixing by melt-2349volatileseparation.EarthandPlanetaryScienceLetters,204,47-60.2350
Pichavant, M., Costa, F., Burgisser, A., Scaillet, B., Martel, C., and Poussineau, S. (2007)2351EquilibrationScales inSilicictoIntermediateMagmasImplicationsforExperimental2352Studies.J.Petrology,egm045.2353
Pistone, M., Arzilli, F., Dobson, K.J., Cordonnier, B.Æ., Reusser, E., Ulmer, P., Marone, F.,2354Whittington, A.G., Mancini, L., Fife, J.L., and Blundy, J.D. (2015) Gas-driven filter2355pressing in magmas: Insights into in-situ melt segregation from crystal mushes.2356Geology.2357
Pistone,M.,Caricchi,L.,Ulmer,P.,Burlini,L.,Ardia,P.,Reusser,E.,Marone,F.,andArbaret,L.2358(2012)Deformationexperimentsofbubble-andcrystal-bearingmagmas:Rheological2359andmicrostructuralanalysis. JournalofGeophysicalResearch:SolidEarth,117(B5),2360B05208.2361
Pitcher,W.S.(1987)Granitesandyetmoregranitesfortyyearson.GeologischeRundschau,236276,51-79.2363
Pitcher,W.S.,Atherton,M.P.,Cobbing,E.J.,andBeckinsale,R.D.(1985)MagmatismataPlate2364Edge:thePeruvianAndes.328p.Blackie,HalsteadPress,Glasgow.2365
Plouff, D., and Pakiser, L.C. (1972) Gravity study in the San JuanMountains, Colorado. US2366GeologicalSurveyProfessionalPaper,800,B183-B190.2367
Poli, S., and Schmidt, M.W. (1995) H2o Transport and Release in Subduction Zones -2368Experimental Constraints onBasaltic andAndesitic Systems. Journal of Geophysical2369Research-SolidEarth,100(B11),22299-22314.2370
Putirka,K.(2008)ThermometersandBarometersforVolcanicSystems.InK.Putirka,andF.2371Tepley, Eds.Minerals, Inclusions and Volcanic Processes, 69, p. 61-120. Reviews in2372MineralogyandGeochemistry,MineralogicalSocietyofAmerica.2373
Putirka,K.D.,Canchola,J.,Rash,J.,Smith,O.,Torrez,G.,Paterson,S.R.,andDucea,M.N.(2014)2374Plutonassemblyandthegenesisofgraniticmagmas:InsightsfromtheGICplutonin2375cross section, Sierra Nevada Batholith, California. American MIneralogist, 99(7),23761284-1303.2377
Read,H.H. (1948)Granites andgranites.Origineof granites,Geological SocietyofAmerica2378Memoir,28,1-19.2379
Read,H.H.(1957)TheGraniteControversy.430p.ThomasMurbyandCo,London.2380Reid,M.R.(2008)Howlongtoachievesupersize?Elements,4,23-28.2381Reid, M.R., and Coath, C.D. (2000) In situ U-Pb ages of zircons from the Bishop Tuff: No2382
evidenceforlongcrystalresidencetimes.Geology,28(5),443-446.2383Reid,M.R.,Coath,C.D.,Harrison,T.M.,andMcKeegan,K.D.(1997)Prolongedresidencetimes2384
for the youngest rhyolites associated with Long Valley Caldera; 230Th- 238U ion2385microprobe dating of young zircons. Earth and Planetary Science Letters, 150(1-2),238627-39.2387
ReviewMUSH 4/19/2016 95
Reiners,P.W.,Nelson,B.K.,andGhiorso,M.S.(1995)Assimilationoffelsiccrustanditspartial2388meltbybasalticmagma:thermallimitsandextensofcrustalcontamination.Geology,238923,563-566.2390
Reubi,O.,andBlundy,J.(2009)Adearthofintermediatemeltsatsubductionzonevolcanoes2391andthepetrogenesisofarcandesites.Nature,461,1269-1273.2392
Richter, F.M., Davis, A.M., DePaolo, D.J., and Watson, E.B. (2003) Isotope fractionation by2393chemicaldiffusionbetweenmoltenbasaltandrhyolite.GeochimicaetCosmochimica2394Acta,67(20),3905-3923.2395
Rivera, T.A., Schmitz, M.D., Crowley, J.L., and Storey, M. (2014) Rapid magma evolution2396constrained by zircon petrochronology and 40Ar/39Ar sanidine ages for the2397HuckleberryRidgeTuff,Yellowstone,USA.Geology,42(8),643-646.2398
Rudnick,R.L.(1995)Makingcontinentalcrust.Nature,378,571-578.2399Savage, P.S., Georg, R.B., Williams, H.M., Burton, K.W., and Halliday, A.N. (2011) Silicon2400
isotope fractionation duringmagmatic differentiation. Geochimica et Cosmochimica2401Acta,75(20),6124-6139.2402
Scaillet, B., Clemente, B., Evans, B.W., and Pichavant, M. (1998a) Redox control of sulfur2403degassinginsilicicmagmas.J.geophys.Res.,103(B10),23937-23949.2404
Scaillet,B.,andEvans,B.W.(1999)The15 June1991eruptionofMountPinatubo. I.Phase2405equilibria andpre-eruptionP-T-fO2-fH2Oconditionsof thedacitemagma. Journal of2406Petrology,40(3),381-411.2407
Scaillet,B.,Holtz,F.,andPichavant,M.(1998b)Phaseequilibriumconstraintsontheviscosity2408of silicic magmas 1. Volcanic-plutonic comparison. Journal of geophysical research,2409103(B11),27257-27266.2410
Schmitt, A.K., Lindsay, J.M., de Silva, S., and Trumbull, R.B. (2003) U-Pb zircon2411chronostratigraphy of early-Pliocene ignimbrites from La Pacana, north Chile:2412implicationsfortheformationofstratifiedmagmachambers. JournalofVolcanology2413andGeothermalResearch,120(1-2),43-53.2414
Schmitt,A.K.,Stockli,D.F.,Lindsay,J.M.,Robertson,R.,Lovera,O.M.,andKislitsyn,R.(2010a)2415Episodic growth and homogenization of plutonic roots in arc volcanoes from2416combinedU–Thand(U–Th)/Hezircondating.EarthandPlanetaryScienceLetters,2417295(1–2),91-103.2418
Schmitt,A.K.,Wetzel,F.,Cooper,K.M.,Zou,H.,andWorner,G.(2010b)MagmaticLongevityof2419Laacher See Volcano (Eifel, Germany) Indicated by U–Th Dating of Intrusive2420Carbonatites.JournalofPetrology,51(5),1053-1085.2421
Schoene,B.,Schaltegger,U.,Brack,P.,Latkoczy,C.,Stracke,A.,andGunther,D.(2012)Rates2422ofmagmadifferentiationandemplacement inaballooningplutonrecordedbyU-Pb2423TIMS-TEA, Adamello batholith, Italy. Earth and Planetary Science Letters, 355-356,2424162-173.2425
Seaman, S.J. (2000)CrystalClusters, FeldsparGlomerocrysts, andMagmaEnvelopes in the2426AtascosaLookoutLavaFlow,SouthernArizona,USA:RecordersofMagmaticEvents.2427JournalofPetrology,41(5),693-716.2428
Shane,P.,Smith,V.,andNairn,I.(2005)Hightemperaturerhyodacitesofthe36kaHauparu2429pyroclastic eruption, Okataina Volcanic Centre, New Zealand: Change in a silicic2430magmaticsystemfollowingcalderacollapse. JournalofVolcanologyandGeothermal2431Research,147,357-376.2432
ReviewMUSH 4/19/2016 96
Shibano,Y.,Namiki,A.,andSumita,I.(2012)Experimentsonupwardmigrationofaliquid-2433rich layer in a granular medium: Implications for a crystalline magma chamber.2434Geochemistry,Geophysics,Geosystems,13(3),Q03007.2435
Shimizu,A.,Sumino,H.,Nagao,K.,Notsu,K.,andMitropoulos,P.(2005)Variationinnoblegas2436isotopic composition of gas samples from the Aegean arc, Greece. Journal of2437VolcanologyandGeothermalResearch,140(4),321-339.2438
Shinohara,H.(2008)Excessdegassingfromvolcanoesanditsroleoneruptiveandintrusive2439activity.ReviewsofGeophysics,46,RG4005.2440
Shirley,D.N.(1986)Compactioninigneouscumulates.JournalofGeology,94,795-809.2441Sillitoe,R.H.(2010)PorphyryCopperSystems.EconomicGeology,105(1),3-41.2442Simakin,A.G.,andBindeman,I.N.(2012)Remeltingincalderaandriftenvironmentsandthe2443
genesisofhot,recycled,rhyolites.EarthandPlanetaryScienceLetters,337-338,224-2444235.2445
Simkin, T. (1993) Terrestrial Volcanism in Space and Time. Annual Review of Earth and2446PlanetarySciences,21,427-452.2447
Simon, J.I., and Reid, M.R. (2005) The pace of rhyolite differentiation and storage in an2448"archetypical" silicic magma system, Long Valley, California. Earth and Planetary2449ScienceLetters,235(1-2),123-140.2450
Simon,J.I.,Renne,P.R.,andMundil,R.(2008)Implicationsofpre-eruptivemagmatichistories2451of zircons forU-Pb geochronology of silicic extrusions. Earth andPlanetary Science2452Letters,266(1-2),182-194.2453
Sinton, J.M., and Detrick, R.S. (1992) Mid-Ocean Ridge Magma Chambers. Journal of2454geophysicalresearch,97(B1),197-216.2455
Sisson, T.W., and Bacon, C.R. (1999) Gas-driven filter pressing inmagmas. Geology, 27(7),2456613-616.2457
Sliwinski, J.T., Bachmann, O., Ellis, B.S., Dávila-Harris, P., Nelson, B.K., andDufek, J. (2015)2458Eruption of shallow crystal cumulates during caldera-forming events on Tenerife,2459CanaryIslands.JournalofPetrology.2460
Smith,R.L.(1960)Ashflows.GeologicalSocietyofAmericaBulletin,71,795-842.2461Smith,R.L.(1979)Ash-flowmagmatism.GeologicalSocietyofAmericaSpecialPaper,180,5-2462
25.2463Smith, R.L., and Bailey, R.A. (1968) Stratigraphy, structure, and volcanic evolution of the2464
JemezMountains,NewMexico.SpecialPaper-GeologicalSocietyofAmerica,447-448.2465Soden,B.J.,Wetherald,R.T.,Stenchikov,G.L.,andRobock,A.(2002)GlobalCoolingAfterthe2466
Eruption of Mount Pinatubo: A Test of Climate Feedback byWater Vapor. Science,2467296(5568),727-730.2468
Solano,J.M.S.,Jackson,M.D.,Sparks,R.S.J.,Blundy,J.D.,andAnnen,C.(2012)MeltSegregation2469in Deep Crustal Hot Zones: a Mechanism for Chemical Differentiation, Crustal2470AssimilationandtheFormationofEvolvedMagmas.JournalofPetrology.2471
Sparks,R.S.J.,Huppert,H.E., andTurner, J.S. (1984)The fluiddynamicsof evolvingmagma2472chambers.PhilosophicalTransactionsoftheRoyalSocietyofLondon,310,511-534.2473
Sparks, R.S.J., and Marshall, L.A. (1986) Thermal and mechanical constraints on mixing2474betweenmaficandsilicicmagmas.JournalofVolcanologyandGeothermalResearch,247529,99-124.2476
Sparks, R.S.J., Sigurdsson, H., and Wilson, L. (1977) Magma mixing: A mechanism for2477triggeringexplosiveeruptions.Nature,267,315-318.2478
ReviewMUSH 4/19/2016 97
Spera,F.J.,andBohrson,W.A.(2001)Energy-constrainedopen-systemmagmaticprocessesI:2479Generalmodelandenergy-constrainedassimilationandfractionalcrystallization(EC-2480AFC)formulation.JournalofPetrology,42(5),999-1018.2481
Spera, F.J., andBohrson,W.A. (2004)Open-SystemMagmaChamberEvolution: anEnergy-2482constrained Geochemical Model Incorporating the Effects of Concurrent Eruption,2483Recharge, Variable Assimilation and Fractional Crystallization (EC-RAXFC). J.2484Petrology,45(12),2459-2480.2485
Spera,F.J.,Borgia,A.,Strimple,J.,andFeigenson,M.(1988)Rheologyofmeltsandmagmatic2486suspensions: 1. Design and calibration of concentric cylinder viscometer with2487applicationtorhyoliticmagma.JournalofGeophysicalResearch:SolidEarth,93(B9),248810273-10294.2489
Spera, F.J., Oldenburg, C.M., Christiensen, C., and Todesco, M. (1995) Simulations of2490convection with crystallization in the system KAlSi2O6-CaMgSi2O6: Implications for2491compositionallyzonedmagmabodies.AmericanMIneralogist,40,1188-1207.2492
Steck,L.K.,Thurber,C.H.,Fehler,M.C.,Lutter,W.J.,Robbert,P.M.,Baldrige,W.S.,Stafford,D.G.,2493andSessions,R.(1998)CrustalandmantlePwavevelocitystructurebeneathValles2494caldera, New Mexico: Results from the Jemez teleseismic tomography experiment.2495Journalofgeophysicalresearch,103,24301-24320.2496
Storm,S.,Schmitt,A.,Shane,P.,andLindsay,J.(2014)Zircontraceelementchemistryatsub-2497micrometer resolution for Tarawera volcano, New Zealand, and implications for2498rhyolitemagmaevolution.ContributionstoMineralogyandPetrology,167(4),1-19.2499
Storm,S.,Shane,P.,Schmitt,A.,andLindsay,J.(2012)Decoupledcrystallizationanderuption2500histories of the rhyolite magmatic system at Tarawera volcano revealed by zircon2501agesandgrowthrates.ContributionstoMineralogyandPetrology,1-15.2502
Streck, M.J. (2014) Evaluation of crystal mush extraction models to explain crystal-poor2503rhyolites.JournalofVolcanologyandGeothermalResearch,284,79-94.2504
Sutton,A.N.,Blake,S.,Wilson,C.J.N.,andCharlier,B.L.A.(2000)LateQuaternaryevolutionof2505ahyperactiverhyolitemagmaticsystem:Taupovolcaniccenter,NewZealand.Journal2506oftheGeologicalSociety,London,157,537-552.2507
Szymanowski,D., Ellis, B.S., Bachmann,O., Guillong,M., andPhillips,W.M. (2015)Bridging2508basalts and rhyolites in the Yellowstone-Snake River Plain volcanic province: The2509elusiveintermediatestep.EarthandPlanetaryScienceLetters,415(0),80-89.2510
Tanaka,H.K.M.,Kusagaya,T.,andShinohara,H.(2014)Radiographicvisualizationofmagma2511dynamicsinaneruptingvolcano.NatCommun,5.2512
Tanaka,H.K.M.,Nakano,T.,Takahashi,S.,Yoshida,J.,Takeo,M.,Oikawa,J.,Ohminato,T.,Aoki,2513Y., Koyama, E., Tsuji, H., and Niwa, K. (2007) High resolution imaging in the2514inhomogeneous crust with cosmic-ray muon radiography: The density structure2515below the volcanic crater floor of Mt. Asama, Japan. Earth and Planetary Science2516Letters,263(1-2),104-113.2517
Tappa,M.J.,Coleman,D.S.,Mills,R.D.,andSamperton,K.M. (2011)Theplutonicrecordofa2518silicic ignimbrite from the Latir volcanic field, New Mexico. Geochem. Geophys.2519Geosyst.,12(10),Q10011.2520
Taylor,H.P. (1980)Theeffectsofassimilationofcountryrocksbymagmason18O/16Oand252187Sr/86Srsystematics in igneousrocks.EarthandPlanetaryScienceLetters,47,243-2522254.2523
ReviewMUSH 4/19/2016 98
Taylor, S.R., andMcClennan, S.M. (1981)The compositionandevolutionof the continental2524crust: Rare earth element evidence from sedimentary rocks. Philosophical2525TransactionsoftheRoyalSociety,A301,381-399.2526
Thomas,N.,Tait,S.,andKoyaguchi,T.(1993)Mixingofstratifiedliquidsbythemotionofgas2527bubbles:applicationtomagmamixing.EarthandPlanetaryScienceLetters,115,161-2528175.2529
Thompson, A.B., Matile, L., and Ulmer, P. (2002) Some Thermal Constraints on Crustal2530AssimilationduringFractionationofHydrous,Mantle-derivedMagmaswithExamples2531from Central Alpine Batholiths 10.1093/petrology/43.3.403. Journal of Petrology,253243(3),403-422.2533
Thompson,G.M.,Smith,I.E.M.,andMalpas,J.G.(2001)Originofoceanicphonolitesbycrystal2534fractionation and the problem of the Daly gap: an example from Rarotonga.2535ContributionstoMineralogyandPetrology,142(3),336-346.2536
Thompson, R.N. (1972) Evidence for a chemical discontinuity near the basalt-andesite2537transitioninmanyanorogenicvolcanicsuites.Nature,236,106-110.2538
Till, C.B., Vazquez, J.A., and Boyce, J.W. (2015)Months between rejuvenation and volcanic2539eruptionatYellowstonecaldera,Wyoming.Geology.2540
Truby,J.M.,Mueller,S.P.,Llewellin,E.W.,andMader,H.M.(2014)Therheologyofthree-phase2541suspensions at low bubble capillary number. Proceedings of the Royal Society of2542LondonA:Mathematical,PhysicalandEngineeringSciences,471(2173).2543
Turnbull, R.,Weaver, S., Tulloch, A., Cole, J., Handler, M., and Ireland, T. (2010) Field and2544GeochemicalConstraintsonMafic-FelsicInteractions,andProcessesinHigh-levelArc2545Magma Chambers: an Example from the Halfmoon Pluton, New Zealand. Journal of2546Petrology,51(7),1477-1505.2547
Turner, J.S., and Campbell, I.H. (1986) Convection and mixing in magma chambers. Earth2548ScienceReviews,23(4),255-352.2549
Turner, S., and Costa, F. (2007)Measuring timescales ofmagmatic evolution. Elements, 3,2550267-272.2551
Turner, S., Sandiford,M., Reagan,M., Hawkesworth, C., andHildreth,W. (2010) Origins of2552large-volume, compositionally zoned volcanic eruptions: New constraints from U-2553series isotopes and numerical thermal modeling for the 1912 Katmai-Novarupta2554eruption.JournalofGeophysicalResearch:SolidEarth,115(B12).2555
Tuttle,O.F.,andBowen,N.L.(1958)Originofgranitein lightofexperimentalstudiesinthe2556systemNaAlSi3O8-KAlSi3O8-SiO2.GeologicalSocietyofAmericaMemoir,74,153pp.2557
Valley,J.W.,Cavosie,A.J.,Ushikubo,T.,Reinhard,D.A.,Lawrence,D.F.,Larson,D.J.,Clifton,P.H.,2558Kelly,T.F.,Wilde, S.A.,Moser,D.E., andSpicuzza,M.J. (2014)Hadeanage forapost-2559magma-oceanzirconconfirmedbyatom-probetomography.NatureGeosci,7(3),219-2560223.2561
Vazquez, J.A., and Reid, M.R. (2004) Probing the Accumulation History of the Voluminous2562TobaMagma.Science,305,991-994.2563
Vona,A.,Romano,C.,Dingwell,D.B.,andGiordano,D.(2011)Therheologyofcrystal-bearing2564basalticmagmasfromStromboliandEtna.GeochimicaetCosmochimicaActa,75(11),25653214-3236.2566
Voshage, H., Hofmann, A.W., Mazzucchelli, M., Rivalenti, G., Sinigoi, S., Raczek, I., and2567Demarchi,G. (1990) Isotopicevidence fromthe IvreaZone forahybrid lowercrust2568formedbymagmaticunderplating.Nature,347(6295),731-736.2569
ReviewMUSH 4/19/2016 99
Wager,L.(1962)Igneouscumulatesfromthe1902eruptionofSoufriere,St.Vincent.Bulletin2570ofVolcanology,24(1),93-99.2571
Wager,L.R.,Brown,G.M.,andWadsworth,W.J.(1960)Typesofigneouscumulates.Journalof2572Petrology,1,73-85.2573
Waite, G.P., and Moran, S.C. (2009) VP Structure of Mount St. Helens, Washington, USA,2574imaged with local earthquake tomography. Journal of Volcanology and Geothermal2575Research,182(1-2),113-122.2576
Walker, B., Jr., Klemetti, E., Grunder, A., Dilles, J., Tepley, F., and Giles, D. (2013) Crystal2577reaming during the assembly, maturation, and waning of an eleven-million-year2578crustal magma cycle: thermobarometry of the Aucanquilcha Volcanic Cluster.2579ContributionstoMineralogyandPetrology,165(4),663-682.2580
Walker, B.J., Miller, C.F., Lowery, L.E., Wooden, J.L., and Miller, J.S. (2007) Geology and2581geochronology of the SpiritMountain batholith, southernNevada: implications for2582timescales and physical processes of batholith construction. Journal of Volcanology2583andGeothermalResearch,167,239-262.2584
Wallace,G.S., andBergantz,G.W. (2002)Wavelet-basedcorrelation(WBC)ofzonedcrystal2585populationsandmagmamixing.EarthandPlanetaryScienceLetters,202(1),133-145.2586
Wallace,P.J.(2001)VolcanicSO2emissionsandtheabundanceanddistributionofexsolved2587gasinmagmabodies.JournalofVolcanologyandGeothermalResearch,108,85-106.2588
Wallace,P.J. (2005)Volatiles in subductionzonemagmas: concentrationsand fluxesbased2589on melt inclusion and volcanic gas data. Journal of Volcanology and Geothermal2590Research,140(1-3),217-240.2591
Wallace,P.J.,Anderson,A.T.,andDavis,A.M.(1995)Quantificationofpre-eruptiveexsolved2592gascontentsinsilicicmagmas.Nature,377,612-615.2593
Ward,K.M.,Zandt,G.,Beck,S.L.,Christensen,D.H.,andMcFarlin,H.(2014)Seismicimagingof2594themagmaticunderpinningsbeneath theAltiplano-Punavolcanic complex from the2595jointinversionofsurfacewavedispersionandreceiverfunctions.EarthandPlanetary2596ScienceLetters,404(0),43-53.2597
Wark, D.A., Hildreth, W., Spear, F.S., Cherniak, D.J., and Watson, E.B. (2007) Pre-eruption2598rechargeoftheBishopmagmasystem.Geology,35(3),235-238.2599
Watkins,J.,DePaolo,D.,Huber,C.,andRyerson,F.(2009a)Liquidcomposition-dependenceof2600isotope fractionation during diffusion in molten silicates. Geochemica et2601CosmochimicaActa,73,7341-7359.2602
Watkins, J.M., DePaolo, D.J., Huber, C., and Ryerson, F.J. (2009b) Liquid composition-2603dependence of calcium isotope fractionation during diffusion in molten silicates.2604GeochimicaetCosmochimicaActa,73(24),7341-7359.2605
Watts, R.B., de Silva, S.L., Jimenez deRios, G., and Croudace, I. (1999) Effusive eruption of2606viscous silicic magma triggered and driven by recharge: a case study of the Cerro2607Chascon-Runtu Jarita Dome Complex in Southwest Bolivia. Bulletin of Volcanology,260861(4),241-264.2609
Webster, J.D. (2004) The exsolution of magmatic hydrosaline chloride liquids. Chemical2610Geology,210(1-4),33-48.2611
Weiland, C., Steck, L.K., Dawson, P., and Korneev, V. (1995) Crustal structure under Long2612Valley caldera from nonlinear teleseismic travel time tomography using three-2613dimensionalray.Journalofgeophysicalresearch,100,20379-20390.2614
ReviewMUSH 4/19/2016 100
White, S.M., Crisp, J.A., and Spera, F.A. (2006) Long-term volumetric eruption rates and2615magmabudgets.Geochem.Geophys.Geosyst.,7(doi:10.1029/2005GC001002).2616
Whitney, J.A., and Stormer, J.C., Jr. (1985)Mineralogy, petrology, andmagmatic conditions2617from the Fish Canyon Tuff, central San Juan volcanic field, Colorado. Journal of2618Petrology,26,726-762.2619
Whittington, A.G., Hofmeister, A.M., and Nabelek, P.I. (2009) Temperature-dependent2620thermal diffusivity of the Earth/'s crust and implications for magmatism. Nature,2621458(7236),319-321.2622
Wickham,S.M.(1987)Thesegregationandemplacementofgraniticmagmas.Journalofthe2623GeologicalSociety,London,144,281-297.2624
Wiebe, R.A., Blair, K.D., Hawkins, D.P., and Sabine, C.P. (2002) Mafic injections, in situ2625hybridization, and crystal accumulation in the Pyramid Peak granite, California.2626GeologicalSocietyofAmericaBulletin,114(7),909-920.2627
Wilcock,J.,Longpré,M.-A.,DeMoor,J.M.,Ross,J.,andZimmerer,M.(2010)CalderasBottom-2628to-Top: An Online Seminar and Field Trip. Eos, Transactions American Geophysical2629Union,91(1),1-2.2630
Williams-Jones, A.E., and Heinrich, C.A. (2005) Vapor transport and the formation of2631magmatic-hydrothermaloredeposits.EconomicGeology,100,1287–1312.2632
Wilson, C.J.N. (1993) Stratigraphy, chronology, styles and dynamics of late Quaternary2633eruptions from Taupo Volcano, New Zealand. Philosophical Transactions - Royal2634SocietyofLondon,PhysicalSciencesandEngineering,343(1668),205-306.2635
Wilson,C.J.N.,Houghton,B.F.,McWilliams,M.O.,Lanphere,M.A.,Weaver,S.D.,andBriggs,R.M.2636(1995) Volcanic and structural evolution of Taupo volcanic zone, New Zealand; a2637review.JournalofVolcanologyandGeothermalResearch,68(1-3),1-28.2638
Wilson,L.,andHead,J.W.(1994)Mars:Reviewandanalysisofvolcaniceruptiontheoryand2639relationshipstoobservedlandforms.ReviewsofGeophysics,32(3),221-263.2640
Wolff, J.A., Ellis, B.S., Ramos, F.C., Starkel,W.A., Boroughs, S., Olin, P.H., and Bachmann, O.2641(2015)Remeltingofcumulatesasaprocess forproducingchemicalzoning insilicic2642tuffs:A comparisonof cool,wet andhot, dry rhyoliticmagma systems. Lithos, 236-2643237,275-286.2644
Wolff,J.A.,andRamos,F.C.(2014)ProcessesinCaldera-FormingHigh-SilicaRhyoliteMagma:2645Rb/SrandPbIsotopeSystematicsoftheOtowiMemberoftheBandelierTuff,Valles2646Caldera,NewMexico,USA.JournalofPetrology,55(2),345-375.2647
Wolff, J.A., and Storey, M. (1984) Zoning in highly alkaline magma bodies. Geological2648Magazine,121,563-575.2649
Wolff,J.A.,Worner,G.,andBlake,S.(1990)Gradientsinphysicalparametersinzonedfelsic2650magma bodies: implications for evolution and eruptive withdrawal. Journal of2651VolcanologyandGeothermalResearch,43,37-55.2652
Worner,G.,andSchmincke,H.U.(1984)MineralogicalandChemicalZonationoftheLaacher2653SeeTephraSequence(EastEifel,W.Germany).JournalofPetrology,25(4),805-835.2654
Worner, G., and Wright, T.L. (1984) Evidence for magma mixing within the Laacher See2655magma chamber (East Eifel, Germany). Journal of Volcanology and Geothermal2656Research,22(3–4),301-327.2657
Wotzlaw, J.-F., Bindeman, I.N., Watts, K.E., Schmitt, A.K., Caricchi, L., and Schaltegger, U.2658(2014)Linkingrapidmagmareservoirassemblyanderuptiontriggermechanismsat2659evolvedYellowstone-typesupervolcanoes.Geology.2660
ReviewMUSH 4/19/2016 101
Wotzlaw, J.-F., Schaltegger,U., Frick,D.A.,Dungan,M.A.,Gerdes,A., andGunther,D. (2013)2661Tracking the evolution of large-volume silicic magma reservoirs from assembly to2662supereruption.Geology,41,867-870.2663
Yoshinobu, A.S., and Barnes, C.G. (2008) Is stoping a volumetrically significant pluton2664emplacementprocess?:Discussion.GeologicalSocietyofAmericaBulletin,120(7-8),26651080-1081.2666
Zajacz, Z., Halter, W.E., Pettke, T., and Guillong, M. (2008) Determination of fluid/melt2667partition coefficients by LA-ICPMS analysis of co-existing fluid and silicate melt2668inclusions:Controlsonelementpartitioning.GeochimicaetCosmochimicaActa,72(8),26692169-2197.2670
Zandomeneghi,D.,Barclay,A.,Almendros,J.,IbanezGodoy,J.M.,Wilcock,W.S.D.,andBen-Zvi,2671T. (2009) Crustal structure of Deception Island volcano from P wave seismic2672tomography:Tectonicandvolcanicimplications.J.geophys.Res.,114(B6),B06310.2673
Zandt,G.,Leidig,M.,Chmielowski,J.,Baumont,D.,andYuan,X.(2003)Seismicdetectionand2674characterizationoftheAltiplano-Punamagmabody,centralAndes.PureandApplied2675Geophysics,160,789-807.2676
Zhang,Y.,andCherniak,D.J.(2010)DiffusioninMineralsandMelts:TheoreticalBackground.2677InY.Zhang,andD.J.Cherniak,Eds.DiffusioninMineralsandMelts,p.5-60.Reviewsin2678MineralogyandGeochemistryvol72.2679
Zollo,A.,Gasparini,P.,Virieux,J.,Biella,G.,Boschi,E.,Capuano,P.,deFranco,R.,Dell'Aversana,2680P.,deMatteis,R.,DeNatale,G.,Iannaccone,G.,Guerra,I.,LeMeur,H.,andMirabile,L.2681(1998) An image of Mt. Vesuvius obtained by 2D seismic tomography. Journal of2682VolcanologyandGeothermalResearch,82(1-4),161-173.268326842685