CALIFORNIA

GEOLOGYA PU8UCATJON OF THE

DEPARTMENT OF CONSERVATIONDIVISION OF MINES AND GEOLOGY

sus. 01 c.won.. PETe WILSONGo~

n. R.sourcaI Agwq DOUGLAS P WHEELERSecre£iJt)l kx Resources

~ 01 c.c.r-- EOW,l,RO G HEIOK>

""Od~

In This Issue IGOLD BEARING QUARTZ VEINS IN THE KLAMATH

MOUNTAINS 35MINING CALIFORNIA CALCITE CRYSTALS FOR THE OPTICAL

RING SIGHT 45LITERARY PROSPECTS 50TEACHER FEATURE 55DMG OPEN-FILE REPORT RELEASES 56PUBLICATIONS REQUEST FORM 57CALIFORNIA GEOLOGY SUBSCRIPTION AND

CHANGE OF ADDRESS FORM 58PRELIMINARY REVIEW MAPS OF PROPOSED SPECIAL

STUDIES ZONES OF JANUARY 1.1993 59

CALIFORNIA GEOlOGY

MAACHlAPRlll993VolUmB 461Number 2

CGeOA 46 (2) 33-60 (1993)

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PubIiaDor'I& _ Io'IIOrmUOn 0It>0I

10\ K StrM\. 141!'l Floot US 14-33SacratMl'lO. CA 95111.-3532(1115) .....S.S716

SouIIwm CaOtDf1ll& RIogIoMl on.:e101 Soult> Broaclway Roon 1065los MgeleI, CA 90012·.uQ2(213) 620-3S60

Bay Aru Regoonal 0Il.e.1,.5 MlI,."e1 51'''1, 3<d FlootSan F,anc::i$.c:O, CA 901103·1513(.'5)5511SOO

CA.lJFORNIA GEOLOGV (ISSN 0026 45551 II pobIosned i)i.

~ tlV the OePfI"mt<'I1 o! ConservaTIOn. OMSIOfl ot 101, ....and Geology n. Records Qtlooe 1$ at 1059 Vine Street, Sulle1OJ, sao........to C'" 9S8'4 S«ond dlIss JIOS1aQII ill paool 8'sacramento, CA POS\mflSl.. Send ..:!d,ess ctIlInges loCAlI·FQflNlAGeOLOGV (USPS3S0840), 80.2980. Sacr........roCA 9S812·298(J

Repons ClltlOIn'WIQ DMsoon of "'onn _~ pt<IjIICl5_ artlOIloI __ ~_ ,ell*, 10 the Nnh ..

~ ... inC*JdId .. 1M maQWIIII ConItollvled~p/>oUlgIr"llh5, _ ~ _ ~..-...g amounce·_..~TtE CONCLUSIONS AHO OPINIONS EXPRESSED IN AR·TlCLES ARE SOLELY THOSE OF THE AUTl«)RS AND AREt«)T NECESSARl.V ENOORSED BY TtE DEPAAT~ENl

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Technoc:aI EOolors

Copy EdllorGtaphlcs and DesignPubloealJOn$ SupeMSOl'

JAMES F DAVISStale Geofo9rst

Elise Maruson

"""" "'"""lena TabolioPeglJY Walker

..18" lambert

NATIONAL EARTHQUAKE CONFERENCE IN MEMPHIS

May 3-5. 1993

RedJcing eanhquake hazards in the central and eastern United Slates isthe theme for this conference. The focus will be on me last decade·s effons totransfer seismologkal assessment and earthquake engineering informationfrom Califomia to the rest of the nation to encourage everyone---home0INI"leTS. teachers. building inspectors. poIiticians-to recognize seismichazards and prepare for a mapr eanhquake.

Five topics will be addressed:

• hazard assessment• damage mitigation• preparedness. awareness, and public education• emergency response and recovery• socioeconomic and public policy impacts.

Papers will be presented and workshops conducted throughout this cross­disciplinary conference.

Some sponsors: Central United Stales Earthquake Consonium. FederalEmergency Management Agency. National Institute for Standards & Technol­ogy. National Science Foundation. U.S. Geological Survey. and the Tennes·see Valley Authority.

For more information. contact: ROD Consultants. 1206 CrestmoorDrive, Boulder. CO 80303. (303) 494-6131

Cover photo: Interference ligure (aiming reticle) as seen through1M Optical Ring Sight. Photo by CraJg WoJmertJauser.

CORRECTION: MarchlApriI1992, page 49.

The bar scale is incotTect on the map of Califomia·s north coast regk:lnaleanhquake SOI.lrCe zones The scale is 100 short for me distances shown byapproximalely a factor of fiYl!. That Is. the l00-mUe mark should be about20 miles: the end 01 the scale should be marked about 200 kilometefS. IlOl1.000 kiIomelefS.

CAUFOANIA GEOLOGV MARCH APRJlI993

Gold-Bearing Quartz Veins in the Klamath Mountains in theRedding 1 x 2 Degree Quadrangle, Northern California

MILES L. SILBERMAN, Geologist. U.S. Geological Survey, Denver, ColoradoJOANNE DANiElSON, Geologisl. Shasta College, Redding, California

Photo 1. Ribbon texture in quartz vein, Summit Mine, FrOrlCh Guk:h·Deadwood Mining District The ribbons consist of bands ofquartz separated by thin dark seams 01 chloritized, ptylllZed wall rock (black shale or argimtej. The banding IS believed 10 repre­sent successive openings and movement along the fissures that contain the veins. Altha Summit Mme, the veins cut argillite andgraywacke 01 the Bragdon Formation. Gold contents 01 veins from this mine collected during our study were as high as 75 ppm(parts per million) (2.2 ounces per Ion). and arsenic conlents were as high as 10,000 ppm (1 percent). Very high arsenIC eonlemlstypICal of veins hosted in argillite and graywacke in the quartz-veIn districts of the Klamath Mountains_ Phofo by M.L S!lberman.

OUr studies 01 gold-bearing quartzveins of the Klamath MountaIns arepart of the U.S. GeologICal Survey's(USGS) Redcilng 10

I( 2" quadrangleConterminous Uniled Stales MineralAssessment Program (CUSMAP)prOjeCt, initiated by the late John Albersand his USGS colleagues in the early1980s. They. and members 01 aca­demia and the mining industry, pub­lished a summary of the geology andgenesis of massive sulfide copper-zincdeposits ot the West Shasta Districtthat Albers had been studying SlllCethe 1950s (Skinner, 1985).

The project identified regions Withinthe Redding quadrangle favorable lorthe occurrence of mineral deposits. themost important of which have beengold, copper, and zinc. The gold occursmaInly in placer deposils and quartzveIns, the copper and zinc occurmainly in massive sulfide deposits.

We viSited many 01 the mines in lhelarger gold-mining dlstnctS, collectedsamples. and studied the mineralogy andchemiStry 01 the gold-bearing veins (Photo1). These studies helped us establish cri·teria that are favorable lor the occurrence01 gold-vein deposits. and helped us Iden­Iity areas most worthy 01 being pros­pected. The overall assessment 01 thequadrangle's mineral resources is com­plete (Silberman, Hassemer, and Force, inpress; Silberman, Hassemer, Force, andTripp, In press).

In thiS artICle we summanze the geo­logiC sertlng, production. mineralogy.geochemistry, and hIstory of mining lode­gold deposits In the Redding quadrangle.A more detailed presentahon of the char­aclerislics and geochemIstry of the gold­bearing veins in the major districts canbe round In USGS Open-File Report91·595 (Silberman and Damelson, 1991)...authors.

INTRODUCTION

Tile Redding quadran91e containsparts of three physiogmphic prov­

inces': Coast Ranges. Klamath Moun­tains. and Great Valley (FIgure 1). TheCoast Ranges and Klamath Mountains arepart of the complex of accreted ter­ranes fonning the margin of NorthAmerica from Alaska to Mexico (Coneyand others. 1980). The process of joiningthese terranes to the Nonh American landmass, in the region of northern California.probably began in the Devonian and wascomplete by the Late Cretaceous or earlyTertiary (Blake and Harwood. 1989:Irwin. 1989). The Great Valley provinceextends from near Redding south to theTehachapi Mountains. Made of Jurassicto Holocene sedimentary rocks and sedi­ments (Hackel. 1966). it is an elongatedown-warp. or syncline, formed alterthe accretion of the Coast Range andKlamath Mountains to Nonh America.

• Te,ms in boldface JyPfI are In the glQSsaryon page 43

CALIFORNIA GEOlOGY MARCH/APRIL 1993 35

1lle gold deposits described here arein the Klamath MOUIltains. More than 3million ounces of gold has been producedfrom several terranes within the KlamathMountains province, mostly in the easternhalf of the Redding quadrangle. In thisprovince, which extends into Oregon.about tvJo-thiros of the gold produced wasfrom placer deposits. The most commonIode-gold deposits are mesothennaJquartz or quartz-car"bonate veins similarto tOOse of the Mother Lode belt to thesoutheast (Albers. 1966: Silbennan andDanielson, 1991). Most of the rest of the

lode gold produced was a byproductfrom copper-zinc massive sulfide depositssuch as those of the West Shasta District(Albers. 1966). Additionally. a small quan­tity of gold was from copper-bearingquartz-sulfide and sulfide veins in ultra­mafic rocks (serpentinite) in the west­ern half of the quadrangle. This type ofdeposit is cormnon but not weD studied(Eric. 1948: Silberman and Danielson.199 I). Because the goId-quartz veins arethe most common source of lode gokl. itis likely they are the principal source ofgold in the placer deposits (Clark. 1970).

GENERAL GEOLOGY

1he southern Klamath Mountainsin the Redding lOx :P quadrangle area series of terranes that lie as generallyea5tward-dipping plates separated bythnast faults (Irwin 1981. 1985)(Figure 1). The terranes consist of islandarc and oceanic volcanic and sedimen­ta'Y rocks including sandstone. mudstone.shale, greenstone. chert. minor lime­stone. and these rocks' metamorphicequivalents. that fomled in Ordovicianthrough Jurassic time. 1he Eastern

'~I__:.,,:-_~'-,,---,'C,,,::,~.Mileso 2 • 61(~

Volcanic Rocks 01

Lode gokl depos~ with greaterthan 5,000 ounces production

La Grange Mme (largest placerdeposit In Klamath Mountains)

Approximate boundary 01 goldmining distrICt

The Greal Valley

+

Younger Sedunentary

.."

LEGEND

Plutons thatlnlruded beforeitCCfet;on oIlerranes

Physiographic ptOVlIlce

""'......

PllItons thalml1Uded alterac:c:rebon 01 terranes••

PROVINCES

'0":..· ...."r

Terranes madeITI05Ify 01:

• Oceanic rocks

D Rocks lomllld In Island,,~

~-;..'?'.

0,

'~•"0'.,l''?...

•

............

Terrane boundasy ApproXlrnate botindary 01copper-zinc district

Figure 1. Generalized geology of the Redding 10 II 2" quadrangle showlTlg pre- and post·accretlon plUlons. lode gold mining diSlricts. majorcopper-zinc districts, and gold·quartz vein mines With greater than 5.000·ounce productIOn. Lode mine locations Irom Hotz (1971). Terranes:EKT. Easlem Klamath: n. Trimty: CMT. Central Metamorphic: NFT. Northfork: HT. Hayfork: RCT. Ranlesnake Creek: WJT. WesternJurassIc. Modified from Fraricelll and orhers (ISB7).

36 CALIFORNIA GEOLOGV MARCH APRIL 1993

,•Eureka

PAC/FICOCEAN

Glen Creek Beh(Lale JuraSSIC

:- ISO m.y.)

EXPLANATION

Plutonic Belts

flIT] Intruded alter terraneswere JOined

Ironside Mountain Beh(mid-Middle Jurassic

::' 170m.y.)

McCloud Belt(Permian

::- 255 my.)

Mule Mountain Stock(Devoman

:' 400 m.y.)

Shasta Baity Bell(Early C,etaaJOUS

:-136 m.y.)

~ Inlruded belore terranes~ were loined

-- Outline of individual pluton

Star Mountain Belt·'-.o:,,,,,­(Early Jurassic

::- 200 m.y.)

""L ~ ~ --'

Figure 2. Map of the Klamath MountainS in the Redding 1 x 2 quadrangle prOVlllce showing outlines 01 major plutons and trends ofplutonic belts. Modified from Irwin (1985).

Klamath Terrane (Hgure l}. the part ofthe Klamath Mountains to which theother terranes were joined. formed dur­ing a period of volcanic-arc activity thatextended from Devonian through Jurassictime {Irwin. 1981). This Eastern KlamathTerrane was built on Ordovician oceaniccrust and upper mantle. IlOVJ representedby the Trinity Terrane, The Central Meta­morphic Terrane developed along thewestern edge of the Eastern KlamathTerrane during Devonian subductionbeneath the Trinity Terrane. Subse­quently. during Middle 10 Late Jurassictime. the Northfork. Hayfork. RattlesnakeCreek. and Western Jurassic terraneswere pined to the combined EasternKlamath and Central Metamorphic ter·ranes by successive subduction events(Irwin. 1981. 1985).

Defonnation dUring accretion led todismemberment. remobilization. and em­placement of ultramafic rock (With alter­ation to serpentinite) along many terraneboundaries. The ultramafic rocks areophiolites formed from the deeper partsof the oceanic and island arc terranes.Because serpentinite bodies are stronglymagnetic. aeromagnetic maps delineate

subsurlace boundaries extending \.Veilbeyond the outcrops (Griscom and others.in press).

Granitic and mafic plutons and associ­ated hypabyssal rocks of Devonianthrough Cretaceous age intrude the rocksof the terranes. Many of these plutons arein belts that generally follow the trends 01the joined terranes (Irwin. 1985: Agure2). Some intrusive bodies were emplaced\.Vithin the host terrane before anotherterrane was attached. Most of these areparts of ophiolites or are comagmaticwith volcanic rock sequences that formedin the same island arc. An example ofthe latter is the Micklle Jurassic IronsideMountain Batholith belt in the HayforkTerrane. which is comagmalic with aregionally extensive meta·andesite unitthat underlies much of the terrane (Irwin.1985; rlgure 2).

Some plutons and plutonic beltsclearly intruded after terranes joined;either lhey are significantly younger thanthe rocks lhat surround them. as deter·mined by isotopic daling. or they cutacross terrane boundaries (Irwin. 1985).The Early Cretaceous Shasta Bally

Batholith and the belt of plutons in whichil is found are post-joining (In.dn. 1985:rtgure 2).

The regional metamorphic grade ofthe volcanic and sedimentary rocks ofthe tem'lnes ranges from unmetamor­phased. through lov..>-grade (greenschistfacies). to moderate-gracle metamor­phism (amphibolite facies). Metamor·phosed rocks of variable grade are inevery terrane (Davis. 1966). Contactmetamorphism has affected rocks ad}il'cent to plutons. particularly post-joiningintrusions. as exemplified by the bandedgneiss zones along the contacts of theShasta Bally Batholith and the countryrock (Albers. 1964).

Superjacent rocks include Creta­ceous and Tertiary sedimentary and volca­nic rocks. Most 01 these are in the GreatValley province (F"Lgure I).

Most of the terranes of the KlamathMountains province have similar litholo­gies. although the prO]'Xlrtions of therock types differ. A lew. such as theRalliesnake Creek (mostly dismemberedophiolite) and Central Metamorphic

CAUFORNIA GEOlOGY MARCH APRIL \993 37

(a complex of mafic and felsic gneiss andschist) terranes, are exceptions. Someterranes. such as the Northfork Terraneand the eastern part of the Hayfork Ter­rane. are melanges of varied oceanic orisland-arc rock types in a shaly matrix.FraticelH and others (1987) describedindividual fonnations. including plutons.in the terranes (Figure 1).

LODE-GOLD DEPOSITS OF THEKLAMATH MOUNTAINS

History

Gok:I was discovered in the KlamathMountains in 1848 by Major Pierson B.Reading. Reading was a colorful characterwho participated in the Bear Rag Revolt.and prior to his diSCO\lery of gold. workedat Sulter's Fort and visited the MarshallMill at the Coloma gold discovery site in

the Sierra Foothills (Shasta COW1ty His­torical Society. written communication,1991). In the literature there is somedisagreement about the location of theKlamath discovery site. Ferguson (1912)and Hotz (1971) quoted an earlier reportby Raymond (1874) that indicates Read­ing made the discovery along Clear Creekin Shasta County. Brovm (1916) andIrwin (1960) suggested, however. thatReading discOV(!red gold earlier. along theTrinity River near Douglas City. TrinityCounty. From the description in Brown(1916), it seems that Reading was the firstto find gokl at lx>th sites.

At first. gold was produced primarilyfrom placer deposits. The first lode min­ing in the Klamath Mountains was atthe Washington Mine in French Gukhin 1852. Placer mining led to the discov­ery of gokl- and silver-bearing gossans

(oxidized parts of the massive sulfidedeposils) that lAleT"e first mined in the1860s (Photo 2). Lode-gold productionlagged far behioo that of placer unlilthe1880s. From then until World War I.at least as much gold was produced byquartz-lode mining as by placer mining.wid production dropped considerablyin the 19205. During the 19305 the bulkof gold extraction was from dredgingoperations, although quartz-lode miningactivity continued and mining of gossansfor gold increased (Albers. 1966). In1942, gold production was stopped forthe duration of the war by PresidentRoosevelt's Executive Order. II neveragain reached prior levels.

Small-scale and recreational placermining continues in the Klamath Moun­tains. but most quartz-lode mines. particu­larly in the Redding quadrangle. are inac­tive. 1llere is development. exploration.and small-scale mining, hoI.uever. at theWashington Mine. the Klamath Moun­tains' earliest producer. aoo the SummitMine. both in the French Gukh District.aoo at the Yankee John Mine. near 19o.in the Shasta-Redding District. Explora­tion aoo development wcre carried outat the Reid Mine. Old Diggings Districlin the mid-1980s, but the mine is nowinactive.

The placer deposits. some of VJhichcontain minor platinum and platinumgroup elements. are along the major riv­ers and their tributaries, particularly theTrinity and Klamath rivers. and OearCreek. Tertiary aoo Quaternary graveldeposits have produced gold, as havebeach deposits along the coast in DelNorte and Humooldt counties. in theCoast Ranges province Orwin. 1960:Oark. 1970: HOlz. 1971). One of thelargest placer mines in the United Stalesis in the Klamath Mountains. at the LaGrange deposit (Figure 1) in the CentralMetamorphic Terrane. near Weaverville.It was active intermittently from 1861through the 19405 and produced390.000 ounces of gold (Oark. 1970).

Photo 2. Massive pyrite. lower leh. and gos­san. or iron o~lde. upper nght.lormed by theoxidation 01 the pyrite durnlQ weathering.Bnck Ftat ore body, Iroo Mountain Mine.West Shasta Copper·Zinc District. Pharo byM.L. Silberman.

38 CALIFORNIA GEOLOGY MARCH APRIL 1993

The Old Diggings District. which isbetween the Devonian MuleMountain Stock and the Per­mian McCloud belt intrusions.including the Pit River Stock(ptgures I and 2), appears tocorroborate the suggestionthat important districts arebet\ll€en plutonic belts. How­ever. a recent K-Ar age deter­mination on sericilic alterationadjacent to one of the largeveins at the Reid Mine shaIN'Sthat the mineralization isDevonian. and approximatelythe same age as the MuleMountain Stock (Photo 4)(Danielson and others. 1990).

Production

Although similar island arcterranes are present in theVJestem Klamath Mountainsin the Redding quadrangle(P'9ure 1). no large veindeposits have yet been identi­fied there. HOI.'Je\IeT. small.goId-quartz and gold-coppersulfide-rich vein systemsabound. and there has beenconsiderable placer mining. Infact. there are placer golddeposits throughout the Kla­

math Mountains and they are not re­stricted to lode mine areas (hwin, 1960:Hotz. 1971).

More than half of the 7 miRion ouncesof gold produced from the Klamath Moun­tains (64 percent) was from placer depos­its. Gold-bearing quartz veins produced27 percent. and the remaining 9 percentwas produced as a byproduct of copper­zinc massive sulfide smelting. The develop-

wood and other districts in the EasternKlamath Terrane. ranges in compositionfrom quartz diorite to diorite and is ofseveral different ages (Photo 3) (Danielson.1988).

Districts such as South Fork. CanyonCreek-East Fork. Hayfork. and HarrisonGulch probably are within individual p1u·tonic belts rather than bet\ll€en them. AtCanyon Creek-East Fork. quartz por­phyry. pegmatite. aplite. and diorite areassociated with many of the quartz veins(Hou. 1971; Hotz and others. 1972).

belt; in the Hayfork Terrane. the districtsare within the Ironside Mountainbelt.

belts, plutons. and hypabyssal intrusions.The most productive mines in these dis­tricts are between the pre-joining. Dev0­nian Mule Mountain Stock and the post­joining. Early Cretaceous Shasta BallyBatholith. The gold-bearing quartz veinsare closely associated Wlth dikes and sillsof quartz porphyry. quartz dk>rite. anddiorite (Albers. 1%5; Danielson andSilberman. 1988). The "birdseye M por­phyry described by Albers (1961. 1%5).so frequently associated with gold-bearingquartz veins at the French Gulch-Dead-

In most of the gold-mining districts.two or more petrographically distinct setsof intermediate to felsic hypabyssal intru­sions are spatially associated with thegold-bearing quartz veins. These dikes andsills are believed to be offshoots of thelarger plutonic bodies (Hotz. 1971:Danielson and Silberman. 1988). TheFrench Gulch-Dead'.VOCXl District. whichwas the largest gold producer in theKlamath Mountains. and the nearbyVJhiskeytown District are good examplesof the relationships between plutonic

Photo 3. Birdseye porphyry dike. French Guk:h·Deadwood District.Gold-bearing quartz veins are associated With these dikes and fre­quently contained Within lhem. The dikes vary in compoSition fromdaCite to diorite. but all compositional vanelles contain the largerounded plagioclase phenocrysts or birdseyes shown above. Theassociation between dikes and quartz veins is so marked that pros­pectors were advised to search all contacts 01 the birdseye porphy­ry dikes to lind minera~zed veins. The dikes are believed to beoffshoots 01 the Shasta Bally and other plutons (Danielson. 1988).K-Ar dallng suggests that at least some of the dikes are approxi­mately 160 rna (JurassIc). older than the early Cretaceous ShastaBally Batholith. Photo oy Joanne Damelson.

We suggest that most ofthe productive gold-bearingquartz-vein districts are situ-ated between pre- and post-joining plutonbelts and are within a few miles of thecontact between their nost rocks and oneor more granitic plutons (Danielson andSilberman. 1988). This associatk>n ismost evident in the Eastern Klamath Ter­rane where many of the quartz-vein dis­tricts are between the Cretaceous ShastaBally belt and either the Oe\.a1ian MuleMountain Stock or plutons belonging tothe Permian McCloud belt (Ptgures 1 and2). In the Central Metamorphic Terrane.the districts are within the Shasta Bally

Lode gold deposits 01 the KlamathMountains are primarily in the easternpart of !he province in terranes contain­ing metavolcanic and metasedimentaryrocks generated in island arcs (Figure 1).The most common lode deposits arequartz or quartz-carbonate veins similarto those of the Mother Lode (Silbermanand Danielson. 1991). with productiontotals varying from a few tens of ouncesto more than 400.000 ounces. Massivesulfide deposits hosted in volcanic rocksand gold-bearing skarn depos­its have produced less lodegold (Hou, 1971). The largemines are in quartz-vein sys­tems. for example the BrownBear Mine in the FrenchGulch District (Albers. 1965:Hotz. 1971).

GoId-bearing quartz veinsare spatially associated withgranitic plutons of variousages. In most of the largerdistricts. hypabyssal dikes andsills related to the plutons areintimately associated with.and in many places host.gold-bearing quartz veins(Ferguson. 1912: Albers.1%5: Horz. 1971). In addi­tion to the distributKln ofplutons. Ptgure 1 showsquartz-vein deposits that pro­duced more than 5.000ounces of gold in theKlamath Mountains in theRedding quadrangle.

Distribution of Gold-BeanngQuartz Vein Deposits and TheirRelationship to Plutonic Rocks

CALIFORNIA GEOLOGY MARCHiAPAIL 1993 39

Lode Gold Production from Mining Districts and Terranes of the Klamath Mountains.

DISTRICT TERRANE GOLD REFERENCE(ounces)

French Gulch-Deadwood EKT 800.000 1

1,500,000 2

Minersville EKT 39.000 1

Whiskey10wn EKT 54,000 1

70,000 3Backbone EKT 50,000 1

Shasta-Redding EKT 25,000 1,2

Old Diggings EKT 200,000 1

Shasta copper-zinc belt l EKT 560,000 2

Canyon Creek·East Fork GMT 192,000 4

Harrison Gulch HT 200,000 1

Hayfork HT 5,000 1

TOlal 2,125.000 (low estimate)

2,841.000 (high estimate)

EKT • Eastern Klamath TerraneCMT • Central Metamorphic Terrane

HT • Hayfork Terrane

, Mostly byproduct 'rom massive sulfide depoSits. East and West Shasta districts.References f. Hou (1971). 2. Clark "970): 3. Albers (1965): 4. /-Iou and olhers (1972)

ment of copper smelting in 1896 wasimponant for gold production (Albers,1966). Gold-bearing vein quartz from theOld Diggings and other districts was usedas smelter flux. TIle recovery of gold fromthese flux ores and sulfide-copper oresgreatly enhanced gold production in theregion (Aubrey. 1908).

LOOe gold production from miningdistricts in the Redding quadrangle isSlDTlmarized in the table below. Becauseproduction was reponed only in dollaramounts. loVe used gold prices at the timeof mining to calcu1ate production inounces. We estimate that total gold pro­duction from the Redding quadrangle,including kx:Ies and placers. exceeds3 million ounces or almost half the goldproduced in the Klamath Mountains(Silbennan and Danielson, 1991). Theavailable production figures vary consider­ably. We calculated gold produced fromthe French Gulch-Deadwood District, thelargest district in the Klamath Mountains.as 800.000 ounces from Hotz's data(1971). and 1.500,000 ounces fromClark's data (1970). Thorough recordswere not kept during most of the placergold production. In fact. no data werefound from some of the smaller districtssuch as Dog Creek and Bully Choop.

Production data discrepancies forsilver are on the order of 20 millionounces for a single mine (Lydon andO·Brien. 1974). Silver was produced asa byproduct of the copper-zinc massivesulfide deposits and is present with gold inquartz-vein deposits. The South ForkDistrict (Figure 1) had the only significantsilver production from quartz veins. Itproduced about $1 million of silver.mostly before 1900 rrucker. 1926:Albers, 1965).

Geologic Sening

Gold-bearing quartz veins are in avariety of host rocks and geologic seningsthroughout the Klamath Mountains, butthe largest deposilS and the most produc­tive districts are in the Eastern Klamath.Central Metamorphic. and Hayfork ter­ranes (Figure 1). Gold·bearing quartz veinsare common in seven geologic settings.We defined these settings using publisheddescriptions and our obselVations.

1. Steeply dipping veins in greenstonewith or without metarhyolite of Devonian

age. The host rocks are metamorphosedto the greenschist fades. Examples arethe Old Diggings and Dog Creek districlSin the Eastern Klamath Terrane (Hotz.1971).

2. Steeply dipping veins In graywackeand argillite of Late Devonian to earlyCarboniferous age and moderately dip­ping quartz veins along the thrust contactof the graywacke-argillite rocks and under­lying Devonian greenstone (Photo 5).Both selS of veins are associated withdikes and sills of quartz-porphYTY andbirdseye porphyry of diorite to quartzdiorite composition (Photo 3) (Albers.1965: Hotz. 1971). Examples are FrenchGuk:h-Deadwood, Eastman Gulch. andMinersville districlS and parts of theWhiskeytown District. aU in the EasternKlamath Terrnne.

3. Steeply dipping quartz veins in theDevonian Mule Mountain Stock andcomagmatic metarhyolife and greenstonenear contacts with the stock. Examplesare the Shasta-Redding District and pans

of the Whiskeytown District (Albers.1965: Lydon and O·Brien. 1974: Hotz.1971). In the Backbone District. quartzveins are in a Devonian metarhyoolite intru­sion some distance from the contact of theMule Mountain Stock. but we includethem in this category (Lydon and O'Brien,1974).

4. Steeply dipping silver-rich quartzveins in the Early Cretaceous Shasta BallyBatholith. The South Fork District is theonly precious metal. quartz-vein districtin the Klamath Mountains that was silverrich and had Utile gold production (Tucker.1926: Albers. 1965: Hotz. 1971).

5. Gently to steeply dipping quartzveins in amphibolite-facies schist andgneiss. The steeper veins are associatedwith pegmatite, aplite. and quartz por­phYTY dikes (Photo 6). Examples are theCanyoon Creek-East Fork and Bully Choopdistricts in the Central Metamorphic Ter­rane (Ferguson, 1912: Averill. 1941:O·Brien. 1965: Hotz, 1971).

CALIFQANIA GEOLOGY MARCH.APAIL 1993

Photo 4. Banded quartz vem With streaks 01 pyrite and chlorltlzed wallrock inclUSions, Reid Mine, Old Diggings District The vein. which isapproximately 1.5leet (0.5 m) wide (base 01 photo). cuts greenstone otthe Devonian Copley Formation. The lootwall 01 the vein (lower lelt) issheared lor distances 01 up to 6 feet (2 m) trom the vein. Both the hang­ing wall (upper right) and loolwall of the veIn contain Irregular, thin quartzveins. Gold contents as high as 70 ppm (2 ounces per too) were found insamples of the veins collected at Reid Mine. The mineralized valns alsocontarn up to 200 ppm copper. 300 ppm boron. and 21 ppm tellunum.The veins are surrounded by a halo ot saricltlC alteraIJon that yieldeda K-Ar age ot approximately 400 mao indicating the veins were formedin Devonian time, and are related to the same magmatic eptsode thatproduced their host rocks (Danrelsoo and others. 1990). Photo byML Silberman.

6. Steeply dipping quartz veins inargillite and chert of late Paleozoic Of

Jurassic age near the contact with JurassicHayfork Bally Meta-Andesite. Examplesare Hayfork and Harrison Gukh districts(Hotz, 1971). in the Hayfork Terrane.

7. Gold-bearing quartz veins cOlltain­ing copper sulfides and/or disseminatedcopper sulfides and carbonates with orwithout quartz. in serpentinite. diorite.and gabbro in ultramaficrock complexes (Eric.1948). lhese deposits arecommon in many of theterranes of the KlamathMountains and CoastRanges. includingFranciscan terranes. theJosephine Ophiolite of theWestern Jurassic Terrane,the Trinily Terrane, northof the Redding quadrangle.and others that containserpentine and dismem­bered ophiolite. such asthe Rattlesnake CreekTerrane. The most signifi­cant example of thisdeposit type in the Reddingquadrangle is the HorseMountain District.

Quartz veins in theabove settings are generallysimilar. They are mediwnto coarse grained and con­tain variable amounts ofwall-rock fragments andlesser calcite. Ribbon tex­ture. bands of quartz sepa­rated by seams of alteredwall rock. is common inthe veins (Photo ll. Thesulfide mineral content isgenerally low. from lessthan 3 percent to approxi-mately 5 percent. Sulfide contents aremuch higher in the silver-rich veins of theSouth Fork District. Sulfides are generallyconcentrated in wall-rock inclusions andin wall rocks immediately adjacent toveins. Pyrite is the most abundant sulfidemineral. Other sulfide minerals includearsenopyrite (particularly common inargillite-graywacke-hosted veins). galena.sphalerite, chakopyrite. pyrrhotite. andmolybdenite (Hotz. 1971). Gold tellurideminerals are present in veins hosted ingreenstone (MacDonald. 1986). 8emen-

tal gold is present in quartz and sulfideminerals. mainly pyrite 0;012. 1971).

ll'le type of alteration minerals in wall­rock adjacent to the quartz veins dependson host rock lithology. In greenstone.metarhyolite. and granitic rocks. includingdikes and sills. sericilic alteration productsare most common. Chlorite and carbon­ate minerals may also be present. Dikesand sills ad,iacent to veins generally are

silicified and have sericitic alterationslightly farther from the veins. Albiticalteration and cartxlnale minerals arealso common. and paragonite (sodium­bearing mica similar to muscovite) hasbeen reported adjacent to some veins(Ferguson. 1912: Albers. 1%5: Holz.1971). Wall-rock alteration in argillite andgraywacke is not obvious, although localsilicification has occurred adjacent toveins. Petrographic study of wall rocks atthe Summit Mine in French Gulch shows.na..vever. that sericite and chlorite alter

ation minerals and thin cakite or ankeriteveins are commonly developed within afew yards (meters) of the larger gold-bear­ing quartz veins in those host rocks (HelenFolger. USGS. written communication.1986). Hornblende .schist generally ischJoritized adjacent to veins.

Trace element contents of the quartzveins show some differences related tohost rock type. There are also differences

in trace element contents ofveins hosted in the samerock types in different dis­tJicts (Silberman andDanielson. 1991). Silvercontent of mineralizedquartz veins is generally Jessthan 10 ppm. and the gokl­silver ratio generally isgreater than I. The SouthFork District is an exception:silver content of samplesfrom the base metaVsilverveins ranges from 50 to5.000 ppm and the gokl­silV€r ratio is less than0.01. Arsenic content ishighest (>1.000 ppm) inveins hosted by argilliteand graywacke. Tellurium(2-20 ppm) and boron(50-300 ppm) contentsare highest in veins hostedby greenstone. Copper(l0·100 ppm). and lead andzinc (both 10-1.000 ppm)contents are highest outsidethe South Fork District inveins hosted by hornblendeschist in the Canyon Creek­East Fork District. lheseveins also contain an aver­age of 1.2 ppm of mercury.a much higher content thanthat of gold-rich veins fromother rock types and other

mining districts. At Horse Mountain. min­eralized rocks contain more than 2 per­cent copper and high amounts of nickeland chromium (1.500·2,000 ppm).Detailed trace element data from veinsfor many of the mining districts shownin F'19ure 1 are summarized in Silbennanand Danielson (1991).

Origin of Gold-Bearing Ouartz Veins

TIle mineralogy. texture. and associ­ated alteration products of the wall rocks

CALlFQANIA GEOLOGY MARCH-APRIL 1993

plutons or hypabyssal inlrusions. as are many of the mineral­ized quartz veins in the Redding quadrangle.

RESOURCE ASSESSMENT

One 01 the most important methods used in regionalmineral resource assessment is the chemical analysis ofstream sediments. High concentrations of minerals or ele­ments in stream sediments can indicate a deposit of thoseminerals in the drainage basin. From our studies 01 the kxIe­gold deJX>sl15 and analyses of associated stream sediments.VJe were able to identify groups of minerals and elementsthai indicated go1cl deposits.

We found many drainages that contained eithergeochemical or mineral anomalies suggesting gold·lodedeposits throughout the terranes of the western KlamathMOWltains and even in those of the Coast Ranges. We be­lieve these western regions are VJ€1l \.YOrth prospecting be·cause rock types and structures commonly found there arelike those associated with 1ode-go1cl deposits farther east.Descriptions of the areas we think are most likely to containundiscovered deposits will be published this year (Silbemlan.Hasseman. and Force. in press: Silbennan. Hasseman.Force. and Tripp. in press).

Photo 5. Brecciated quartz vein wllh chlorilized, pyritic wall rockinclusions. Summit Mme. French Gulch-Deadwood Mming District.The steep vein cuts argillite and graywacke sandstone o! theMIssisSippian Bragdon Formation. The brecclatJon and texture Indi­cate that the 'issure hosting the quaf\2 vetn moved aller the veinwas initially formed, probably with the Iell wall moVing downwardretallve to the nghl. Brown staJns are iron oxide resulting 'rom theweathering 01 pyrite and other sulfides. Photo by MoL. Silberman.

suggest that these gold-bearing quartzveins are typical mesothermal veins. simi­lar to those in the Mother Lode of Califor­nia southeast of the Klamath Mountains.Stable isotope studies of Mother Lodeveins similar to veins in the Redding quad­rangle suggest they formed from the activ­ity of early. CO2·bearing fluids of deeporigin and later fluids of probable mete­oric origin (BOhlke and Kistler. 1986).

Elder and Cashman (1991) suggested.on the basis of fluid inclusion data. thatmineralized quartz-carOOnate veins at~rtz Hill (in the Oro Ano District 01 thecentral K1amalh Mountains) \.\/eTe fonnedby the partial mixing of IWO fluids. One ofthese fluids was of metamorphic originand the other possibly of meteoric origin.The veins at Quartz Hill are similar tomany of the veins in the Redding quad­rangle: however. the Quartz Hill veins areassociated with a major transcurrentfault (Elder and Cashman. 199 I). Theyare nOI spatially associated with granitic

Photo 6. Ouartz'rlch pegmatite vein cutting hornblende gneiss. upper level of the ChlondeMine, Canyon Creek·East Fork Olstnct. Brown stammg is Irom oxidation of pYrite and othersulfides At Canyon Creek·East Fork. quanz veins are spatially associated With dikes of avanety 0' compoSitionS. Includmg pegmatite. The pegmalltes we collected In Ihls area alefrequently anomalous in gold. but are not economICally mmerallzed Photo by ML SIlberman

CALIFORNIA GEOLOGY MARCH APRIL 1993

ACKNOWLEDGMENTS

We would like to dedicate this paperto three men whose work in the KlamathMountains served as the foundation lormost. if not all. recent studies. The lateJohn Albers initiated the geochemicalstudy of the origin of the gold deposits inthe Klamath Mountains as part of theRedding CU$MAP project of the USGS.John's earlier work. along with that ofW. Porter Irwin on the geology and tec­

tonics. and Preston Hotz on the golddeposits. turned the mystery of the originof the Klamath Mountains into a dynamic.evolving mOOeI. It is \.\lith this mOOeI andtheir inspiration tnat we continue to workon lhe original mission.

Miles l. Silberman is a geologist with the Branch of Geochemistry ofthe U.S. GeologiCal Survey. He has 25 years ellpenence In research andellploralion of base and precious metal deposits in the western United States,Alaska, Mellico. Australia, China. and Israel. In 1982 and 1983, between toursat the USGS, Dr. Silberman deSigned and ran exploration programs for pre­cious metal deposits in the Great BaSin for the Anaconda Minerals Company.Recenlly, he and Joanne Danielson compiled a field gUide to the mineraidepoSits of the eastern Klamath Mountams for the 15th International Meellngoftha Association of Ellploration Geochemists.

Joanne Danielson's geological experience Indudes lielcl work In theAntarctiC and geochemical studies of the moon, Mars. meteorites. kimberlitenodules. and metallferous mineral depoSits.

She teaches geology. earth science, and chemistry at Shasta collegein Redding. California. Her current endeavors Inetude developing anAssociate Science degree, operating a goat dairy. raising pack mules anddonkeys, and researching the mineral deposits of northern California as aUSGS volunteer

GLOSSARY

Acctetion (accteted) - The addillon ofconflnenfal land mass to another confln&ntby colliSIOn.

ComagmaUc -Igneous rocks thaI have acommon set 01 chemICal and mineralogICal'eatures and are denved Irom a commonparent magma An eKampie Irom Reddingis the Mule MOUntaln Stock and BalaklalaRhvohte wtuch occur In the same lerran&and are beheved to be the same age

Facies - tn metafflOfphlSrTl, a group otminerals lormed under certain pressure­temperalure conditions thaI can be usedas an indtealor 01 these conditIOns:

• AmphIbolite faaes- A sUite 01 meta­morphic mln&rals typical of moderate tohlQh pressure (greater than 43,500pounds per square Inch. or 3.000 bars)and tempetatures between 850 and1.300 F (450 and 700 C).

•GreenschIst faoes- A sUite 01 mela­morphlC mmerals typical 0' low to mod­elate pressure and lemperatures 600to 900 F (300' 105OO"C).

Greenstone - Any compact. dark greenaltered or melamorphosed mafic IQneousrock. The color IS from chlorite. actinolite,or epI<tote.

Hypabyssal- An igneous lnlfUSlonbetween p1utontC. which is deep. andsurface volcanIC rocks Dikes. $IUs. andtrregular InlfUSIOl'\S of the Klamath Moun-

tams commonlV assoaated With gold·beanngvems are hVpabvssal inlfUSlOns

Island atc (volcanIc arc) - A genelallycurved belt of volcanoes above a sutJduclionzone. and the volcaniC and plutonIC rocks thatform there. The volcanIC rocks are accompa·nled by sedimentary rocks larmed bV erosion01 the volcanIC rocks

Melange - A bodV 01 rock ctIaract9flzed bytack 01 mtema! contmUity 01 contacls or strataand bV dlsorl9flted blocks 01 alt Slzes (exotICand native) embedded In a matriK 01 linergrained mateflal.

Mesothermal- A hydrothermal rmneraldePOSit found at considerable depfh (probablygrealer than 1 or 2 miles [2 or 3 kmJ) and '"the temperature range of400G 10 800 F (200to 400 C). The term is commonlv used for thetypes 01 gold·quartz verns of the Mother lodeand lhe Klamalh MountainS.

Ophiolite - A sequence 01 rocks character·lZed by ultramafic and malic rocks, IrequenOv8SSOCIafed With deep sea sediments. Theseare segments 01 fhe ocean lloor. IncludmgoceanIC crust and upper mantle rocks, uphftedonto a continent dUfing teHan& col~slotl

PhysIographic province - A legloo whosepallern of land forms IS signlficanliV dillerentIrom that 01 adjacent reglotIS (e.g. GreatValley and Klamath Mountams).

SubdUcllon - The process bV which onelithosphenc plate slides beneath another at aconvergenf contlnenfal margin.

Superjacent sequence or tock - Avounger sequence of rocks situated imme­dlalelV upon or over a lower. older se­quence. as 00 an unconlormlty. In theKlamafh MountaJns. sUper}acent relers10 locks deposited alter the accretionprocesses were complete.

Terrane - A body of rock 01 regIonaledenl characterized bV a geologIC hisforydiller-ent Irom that of adlacent terranesNormallV, faults form lhe boundarybetween adjoining terranes.

Thrustlault - A lault With a dip 0145 degrees or less over much 01 ItS eKlen!.on which the upper plate appears to havemoved upward and over the lower plate

Transcurrent laull- a steeplv Inclined,large-scale. strike-slip lault.

Ultramafic rock - An igneous rock mademostlV 01 the magnesium-iron SilICatemInerals oliVine and pvroxene EKamplesare dunOite (contains mostly olIVIne).pyrOKenite (contains mostly PVfOKeoe),and serpentiOlle (largely made of the ser­pentine group of minerals). These hvdrousmagnesium-iron minerals are formed bylhe alleratlotl of original. non-hvdrousultramafic rocks such as dunmle andpvroKeOlle.

Modififld from~ry 01 Geology. 3td Edition.t987. b,r &ll/$ and Jl'CkJon

CALIFORNIA GEOLOGY MARCH/APRIL t993

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Albers. JP • 1964. Geology 01 the FrenchGulch quadrangle, Shasta and Tnnlty coun·ties. California. U.S. Geological SurveyBulletin 1141-J. 70 p.

Albers, J.P., 1965, EconomIC geology of IheFrench Gulch quadrangle. ShaSla andTrinity counties, CalifornIa: CalltorniaD,v'SIOn of Mines and Geology SpecialReport 85, 43 p.

Albers. J.p. 1966. EconomiC deposns of theKlamath Mountams. In BaIley. E.H" editor,Geology of northern California Californiao.vlSlOn ot Mines and Geology Bulletin 190.p 51-62.

Aubfey. L.E .. 1908. The copper resources ofCalifornia' Calilornla State MIn,ng BureauBulieM SO. 366 p.

Avenll. J.C.• 1941. Minerai resources 01 TnnltyCounty: Calilornla Journal of Mines andGeology. v. 37, no 1. p. 8·89.

Blake, M C., Jr., and Harwood, D.L.. 1989.Teflanes 01 the Northern Coast Ranges.,nBlake, M.C .. Jr., and Harwood. D.L..leaders, TectonIC evolulJon of northernCalifornia: InternatIOnal GeologiCal Con'gress. 28th. Field Tnp GUldebooll. T·108,Amencan GeophySical Union, p. 3·18.

BOhlke, J K., and Kistler, R W., 1986, Rb·Sr,K·Ar, and stable ISOtOpe eVIdence for theages and sources of fluid componenlS ofgold·beanng quartz vems 10 the northernSierra Nevada foothills metamQfphlC bel1,California; EconomiC Geology, v 81,P 296·322.

Brown. G.C.. 1916. The counties of Shasta.SlskJYou. Tnnlty: Report XIV of the StateMineralogiSt. Calilornia Slate MinIngBureau. part 6. p. 746·924

Clark., W.B.. 1970. Gold d,SlrlClS of California'California DIVision 01 Mmes and GeologyBullelin 193. 186 P

Coney, P.J.• Jooes. D.l.. and Monger, J W H"1980. Cord,lIeran suspect terranesNature, v. 288, p. 329·333

Danielson. Joanne. 1988.LJthology andgeochemlSlry of the French Gulch Inlier.Klamath Mounlams, nonhern Calilomla:Calilornia Stale University at ChICO,MS lhesls. 230 p.

Danielson, Joanne. and Silberman, M.L., 1988,GeologIC sening and charactenstics ofgold beanng quartz vems 10 the southernKlamath Mountams, California. In Goode.A.D,T., Smyth. E.L.. Birch. W.O. andBosma. U" oompllers. BICentennialGold '88 EKtended Abstracts, Poster Pro·gram. v. I: GeologICal SOCIety 01 Ausllal,aAbstraCI Sanes. no 23. p. 311·315

Damelson. Joanne. SllbelO13n. M L" andShaflqualla, H.M. 1990, Age of mineral·lzatlon 01 gold·quartz vems at the ReidMme, Shasta County, northern CaliforniaGeological Society of Arnera AbstractsWith Programs. v 22. no 3. p 17.

DaVIS. G A. 1966. MetamorphIC and gramllChistory of the Klamath Mountams, In

Bailey. E H, editor. Geology 01 northernCallforma Callforma DIVISIOn of Minesand Geology Bulletin 190. p. 39·50

Elder. OR. and Cashman, S M, 1991, Tec·tonIC conlrol 01 lode gold depoSl1S, OuartzHIli, Klamath MountainS. California Geo·logical 50aety 01 Amenca Abstracts WIthPrograms. v 23. no 2. p. 21

Eric. J H, 1948, Tabulation of copper depoSits01 California: Califorma 0rv,SlOn 01Mmes and Geology Bullelln t44. part 3.p 197·387

Ferguson, HG., 1912, Gold lodes of TheWeaverville quadrangle. CallformaU S Geological Survey Bullet," 540·A,p 22·79

Fratlcelli, LA. Albers. JP, Irwin. W P.. andBlake. MC. Jr. 1987. GeologIC mapalthe Redding 1 ~ 2 quadrangle. Shasta.Tehama. Humboldt, and TnMy count,es.California: U.S GeoIogal Survey Open·File Report 87·257,18 P

Gnscom, Andrew. Erdman, C.F" and Sauer.P.E.• 10 press, Interpretation of magneticand graVIty maps 01 the Redding I K 2quadrangle, Cahforma-A contnbutlon 10lhe CSUMAP program: U.S GeologicalSurvey Open·Flle Report

Hackel, Otto. 1966. Summary of Ihe geology01 the Great Valley, in Bailey. E H.. editor.Geology of northern CalifornIa CaliforniaDlVlslOn 01 Mmes and Geology Bulletin190. p. 217·238

Hotz. P,E .. 1971. Geology 01 the lode golddepoSits of the Klamath MountainS. Call'forma and Oregon: US GeologICal SurveyButle\Jn 1290,91 P

HOIl. P.E.• Thurber, H K_, Marks, l.Y., andEvans, RK, 1972. Minerai resourcesof the Salmon·Trlmly Alps primitive area,California: US Geological Survey Bullelln1371·B,267p

IrwIn. W P, 1960. GeologIC leconnaissance ofthe northern Coast Range and KlamalhMountains. Calilorma. With a summary ofthe mineral resources: Califorma D,VISIOnof Mines Bulletm 179. 80 P

Irwin. W P.• 1972. Terranes ollhe westernPaleozoIC and TnasslC bell In the southe-rnKlamath Mountains, California: U S Geo·logical Survey ProfeSSional Paper BOO·C.p. C103·C111

Irwin. W.P,. 1981. Tectonic accretion 01 theKlamath Mountains. In Ernst, WG" editor,The geotectonic; developmen! of CahlQfnlaPrenhce-Hall, Englewood Clills, NewJersev. p.29-49

Irwin. W.P" 1985. Age and tectonICS 01 plutonICbellS In accreted terranes 01 the KlamathMountains, California and Oregon. inHowell. 0 G., edllor. TectonostratlQraphlCterranes 01 Ihe Clrcum-Pacllic region:Circum·PaClflc Counollor Energy andMineral Resources. Earth SCience SenesvI.p 187,199

Irwin. W p. 1989, Terranes of lhe KlamathMountalOS, Call forma and Oregon, rnBlake. M,C" Jr.. and Harwood. D.L..leaders, TectonIC evolutIOn 01 northernCalifornia Amencan GeophySICal UflIQn.28th lnternallOnal Geological Congress.Field Tnp GUidebook T·108, p 19·32

Lydon. P A. and O·Brien. JC.. 1974. Minesand minerai resources of Shasta County.Calilorma CallfQfn,a D'VIs,on 01 Minesand Goology County Report 6. 154 p

MacDonald, DC. 1986, Gold and Silver tellu·nde mlnerallzallon allhe Reid Mme.Shasta County, Calilorrua: UnIVerSity ofTennessee at KnOKVllle. MS theSIS, 123 P

O·Bnen. J C" 1965. Mmes and mineralresources 01 TnMy County CaliformaD,VISIOn 01 Mines and Geology CountyReport4.125p.

Raymond, R.W., 1874, StallstlCS of minesand mining In the state and teffllones westof lhe Rocky Mountains: U,S. TreasuryDepartment Annual Report 6. 585 P

Silberman, M.L, and Damelson, Joanne, 1991.GeologIC seltlng, charactenstlCS, andgeochemistry 01 gold beanng quartz V8lnsin the Klamath MountainS In the ReddmgI K 2 degree quadrangle, northern Caflfor·nla: U.S. Geological Survey Open·FlleReport 91-595. 27 P

Silberman, M.L., Hassemer, J R., and Force,Jennifer, m press, Assessment of mmeralresource potenhal 01 lhe eaSlern hall oflhe Redding 12SO.OOO quadrangle. north·western cahlornia: U S. GeologICal SurveyOpen·File Report.

Silberman. M.L, Hassemer, J.R, Force,Jennifer, and Tnpp. R.B, m press, Assess'men! of minerai resource polenllal of thewestern hall 01 the Redding 1:2SO.oooQuadrangle, northwestern Callforma: U SGeologICal Survey Open·Flle Repon.

Silberman, M.L., Hassemer, J.R ,and Smllh.S.M., 1991, Regional geochemical SIgna·tures of lode Au and Cu deposlls In thewestern hall of the Reddmg 1 K 2 quad·rangle. northern California: AsSOCIationof E~p1oratlonGeochemists. 15th Interna·tlonal GeochemICal EKplorallon Sympo·Slum, Programs With Abstracts, p 39.

Skinner, B.J., edItor, t985, A speciallSSUfldevoted 10 maSSive SUU,de dePOSitS. westShasla D,stnct, California: EconomIC Geol·ogy, v 80. no. 8. p 2.067·2287.

Tucker. W.B" 1926. Silver lodes 01 theSoulhlork MlflIng D,SlflCl. Shasta CountyCallforma State Mining Bureau. ReportXXII of the STate MinelaloglSt v 22. no 1,p.201·210.

.. CALIFORNIA GEOLOGY MARCH APRIL 1993

Mining California Calcite Crystalsfor the Optical Ring Sight

LEWIS ORRELL

INTRODUCTION

Soon after the United Slaies entered World War [I.Navy personnel challenged Edwin Land of the

Pol<lroid Corporation to increase the accuracy of certainweaponry. In response. he invented a new gun sightcaned lhe Infinity Sight. Later renamed the Optical RingSight (DRS). it was unique because of the optical char­octerlstics of Us basic element. a wafer of crystaUinecalcite (Photo 1 and inset. page 46). The DRS hadmany advantages over conventional gun sights. A singleunit replaced the Iront and reaT elements. thus eliminat­mg the need 10 align tI.VO gun sight elements with thetarget. The increased speed and precision of sightingwas advantageous because the target was usually movingfast. Furthennore, it was lightweight inexpensive, anddid not require electrical illumination. For these andother reasons. the military applied it to several types ofW€apons (PhOlo 2}.

Rnal acceptance and large production orders materi­alized slowly and. from the beginning of the programto the end. the supply of calcIte crystals was a critkalbottleneck in tne development and procLction of theDRS. In early 1942 there was no working domesticmine for calcite crystals nor a significant proven dep:lsit.yet the military optimistically anticipated using large

Photo 1. Double images of line and circle illustrate birefringence (the sepa·ration 01 a light ray Into two unequally retracted beams) of calcl1e crystal.Pholo by LeWIS Orrell.

Photo 2. T95Hinng a20 mOl anti·alrcraft guneqUipped With an earlyOAS. Photo courtesyof Polaroid CorporalKJll.

quantities for the ORS. This created apredicament. In the absence of large.firm orders. no federal agency coulddivert resources to locate crystals. WHh­out assurance of an adequate. dependablesupply of crystals. it was impru:!enr 10

commH the ORS to combat use aoo toplace large production orders. With char­acleristic decisiveness. land resolved theimpasse by directing his company 10establish a supply of crystals.

The Search for Deposits

Polaroid retained Professor HarryBerman. a mineralogist at Harvard

University. to find suitable sources. Theurgency of wartime did not permit tradi­tional prospecting: Berman needed cluesthat promised immediate results. Afterconsidering several options. he turned 10

Harvard's extensiva mineral collc<:tion.Here he found calcite crystals collected by

CAUrOANIA GEOLOGY MAACHJ"PAtL 1993

John Hilton of Thermal. Callfamia. Hilton. a desert artist. WIlter,and rock seller. had gathered these from a spar location which wasweU knoom among local mineral collectors (Wright. 1957). It waslater named the Palm Wash field or "Hilton Deposil.

M

Berman wasparticularly interested in Hilton's crystals because their growth habit(basal plates) was advantageous lar processing crystals into wafersPhoto 3). Because the optical axes of the flat crystal and wafer werethe same. the shape of the crystals greatly simplified their orientingand slabbing.

Geology of the PalmWash Deposits

The Palm Wash calcite field is near the southern end of theSanta Rosa Mountains in the northeastern comer of San DiegoCounty. It is about 12 miles (19 km) west of the Salton Sea.1-1/2 miles (2.4 Ion) north of County Route S22, and inside theeastern boundary of Anza-Borrego Desert State Park (see map).

During the mining of lhls cakite, the U.S. Geologkal Surveystudied the geology of the deposit three times (Gi1July. 1942;Bramlette and Eakin. 1943; Durrell. 1944). Durrell (1944) statedthat the calcite crystals in the Palm Wash field were found in veinsand pockets in the Palm Spring Fonnation. a mid-Tertiary sedimen­lary clastic (made of rock fragments) formation.

He explained that diastrophic (related to crustal movement bytectonic processes) activity had produced a grid of systems of trans­verse normal faults and longitudinal tension joints. 1lle intersectionsof the faults and joints fanned cavities in which cak:ite was depos·

Edwin Land was the first to recognize that the interferencefigure observed when a calcite crystal is viewed along its opticaxis and between crossed polars (as With a polarizing micro­scope) could be the basis for an improved gun Sight. Theunmodified interference I1gure for calcite consists of a darX crossand a series of concentric colored rings (photo to left). To makethe Navy's Mark 2 version of the CRS, land tOOk a calcitewafer with laces perpendicular 10 the optic axis of the crystal.He cemented polarizing him to each face of the calcite wafer,with the polariZing plane of one lilm at nght angles to the polariz·ing plane of the other. He then inserted this three-layer elementbetween quarter-wave retardatIOn plates 01 a proprietary Pola­roid film. This removed the dark cross by altering the behaViorof light passing through the sight. He then sandwiched the Sightbetween protectIVe layers 01 glass. This 3/16-inch- (O.5-em-)thiCk assembly of simple optical elements left only the concentriCcolored rings in the field of view (cover photo). Land added anexternal red hlter to the f1ng sight assembly that, when movedInto the line of sight. sharpened the rings and changed themto blae!< and red (Wood, 1977). When sighting the target. thecircles (the gun-aiming rellcle) appear to be attne same diS­tance as the target. The CAS enabled the gunner to aim a gunmore rapidly and with less visual strain than with cooventlonalgun sightS. Photo courtesy of Jan Hinsch. Micro/ab, Leica Inc.

Photo 3. Arturo Gonzalez hold1l19 large basal plate crystal atPalm Wash. Photo courtesy of P. BlazovlC,

" CALIFORNIA GEOLOGY MARCH-APRIL 1993

Location map showing the Palm Wash calcite field.

be another year before PresidentROO5e\IE'lt declared optical calcile a criticalmaterial. thereby confening preferredstatus on its supply and suppliers. [n themeantime. the Hoffmans l.VI?I'e left withproduction demands but with lillie help insecuring materials and equipment. How­ever. aid came from the Marines at CampDunlap. who provided drivers. trucks, andrefrigeration for food storage. This unoffi­cial arrangement alJoo.ved the inhospitable.isolated camp to become more productiveand habitable. Raben Hoffman (1944)characterized California cakite mining as~more in the nature of gem extracUon. ~It was aD open trenching instead of W'!der.ground works. There was no 0Yerburdento be rel'llOVed or ores to be blasted.crushed. or chemically processed. Therewere only random vugs (sma! cavities) orseams filled with crystals which had to becarefully exposed and delicately removed.

At first. use of dynamite in breakingout benches was a\'Oided because of theextreme fragility of calcite crystals. Afterexperimenting INith placements of differ­ent charges. Calcite Operators. Inc. intro­duced blasting. It is suspected thaI anindeterminate amount of acceptable crys­tal was tacitly sacrificed lor quicker accessto a greater number of vugs. In the firstmonths of operation, the miners exam·ined and sorted the crystals as they VJereremoved from the seams. utero the crys·talline material was trucked to the camp.acid-.etched. washed. and then gradedfor size and quality. Usable crystals werecarefully wrapped in paper. packed inwooden boxes. and trucked to MarchHeld in San Bernardino where an ArmyAir Force bomber lNhisked them to

The shallow country rock had weath·ered to a soft and friable material whichwas readily excavated with a pick toexpose the seams and vugs. Below thesurface decom(X)Sition. the sandstoneremained hard and removal reqJireddrilling (Hoffman. 1942). This was firstdone with Barro gasoline-~drills(Photo 4). HCMoever. the gasoline enginesproduced toxic fumes in the deep. nanO'Alcuts. Sometime later, the din road 10 themine was rough graded. making it pos.sible to haul a compressor 10 the site.Now 80'pound pavement breaker5 orjack hammers were used instead of thegasoline engines (Hoffman. 1943). thuseliminating the fumes.

.•

,

,"-••

pfOgram for 3 months. HCM'e\Ief. thedemand for crystals outgrew the prOOuc­tivity of the two amateur miners workingthe mine. An organized effort led byexperienced mining engineers wasneeded. Again. l..arKl turned to HanyBerman who contacted felloul Harvardalumni, Robert and Amold Hoffman.The Hoffman brothers had begun theirmining careers by prospecting and stakinggold claims in Canada. By the time ofBennan's approach in October 1942, theHoffmans were intematklnal mining con·sultants and developers of metallic oredeposits. Nonetheless. Berman was ableto recruit them ~for patriotism. not profit~

(Ointon Young, Outlook EngineeringCorporation. oral commlrlication. 1986).

With the country at war. labor andmaterials l.VI?I'e in short supply and accessto both was on a priority basis. It would

Within days. Raben was assessing thePalm Wash field while AmoId was fann·ing a cak:ite mining company. They pro­posed a business plan for developing thefield. Polaroid countered on the same dayand by nightfall, Calcite Operators, Inc.began the nation's first engineered miningof optical cakite.

PA R K

,..

ANZA - BORREGO

,

,

An adequate supply of calcite crystalswas recovered from the Palm Wash cal·dte field to sustain the POOroid ORS

ited by hydrothennal activity. This miner­a.lization was accompanied by wan rockaheration.

DurreD (1944) described the crvstalsas predominantly basal plates. some aslarge as 18 inches (45 em) in diameterand 3 inches (8 cm) in thickness. How­ever, the average size was between 2 and3 inches (5 and 8 cm) in diameter and1/4 to 3/8 inches (6 to 9 mm) in thick­ness. Massive c.ak:ite occurred in veinsseveral inches thick or as a coating on thewalls of Jarge cavities. Because of theprevalenc:e of defects (l\vinning !crystalintergrOMhI. fractures. doudiness) inthe massive calcite. it was of linle or nouse. Crystals that filled spaces. perpen.dicuIar to the walls. were of good quality.although none DurreD found were ofspecimen or optkal gracIe. Hou.oever.since the ORS application tolerated minorimperfections (sub-optic.al grade). thePalm Wash District became an important.usable source.

The Mine Operation

CAliFORNIA GEOLOGY UARCH.APRIL 1993

Photo 4. Young miners openll'IQ Clll along calcite vein with Barco gaSOline-powered drill.Photo courtesy of P. B/azov/(;.

Polaroid. Only crystals that VJere clear andfree of cracks. twinning. and major inclu·sions VJere acceptable. Slight colorationand VJeU-located, tiny inclusions (sub-opti­cal grade) VJere allowable for the ORS.(Where true optical-grade crystals VJerefound during WVJlI, the yield ratk> of sub­optical to true optical crystals was about10; 1,j Crystals v.oere paid for after theywere regraded at me factory, The accep­tance rate VJ<lIS 60 percent.

TIle prevalence of milky or otherwisedefective crystals was such that about 10pounds (4 to 5 kg) of ~usableM crystalsVJere required to obtain 1~ (454 g)of ~acceptable. ~ Raben Hoffman (1944)estimated that Calcite Operators, Inc.had moved 15,000 pounds (6,804 kg) ofrock for each pound of acceptable crys­tals. Durrell (1944) stated mey had re­moved 4,800 cubic yards (3.670 ml)of country rock in making 74 cuts ortrenches, Their total production of almost7,000 pounds (3.175 kg) of acceptedcrystals equated to 1.5 pounds per cubicyard (890 g/m3) of excavation whiletheir successors produced as much as8 pounds per cubic yard (4.8 kg/m3).This may be an adverse reflection on theHoflmans' prospecting or mine manage­ment, or both,

The Palm Wash operation seemedto be going weU as the months wore intomid-summer of 1943. Nevertheless,sometime hetuJeen July and October of1943, the Hoffmans struck the tents,scattered the equipment, abandoned themine, and transferred their operation toMontana.

This was not the end of mining atPalm Wash. however. Jack Frost andBob Dye. who had prospected for CalciteOperators, Inc. at Palm Wash and inMontana. reappeared in the desertedPalm Wash camp In November. Theynegotiated an agreement wim Polaroidand sporadically worked the depositsduring the next year. It is important tonote that their hands-on training andexperience in mining VJ<lIS limited to theseveral months they worked for theHolfmans. Their production records areincomplete. but it can be confidently esti­mated that Polaroid accepted at least3.500 pounds (1,588 kg) of crystals fromthem at a price of $12 per pound. Thiscompares favorably with the Hoffmans'

operation which employed 15to 30 mento produce 7,000 pounds (3.175 kg) ofacceptable crystals at a cost to Polaroid of$17 per pound.

EPILOGUE

By late 1944, computing gun sightsVJere introduced and the need for theORS was minimal. Stockpiles of crystalswere adequate for remaining ORS pro-

duction, so the Navy halted cak:ite crystalmining. New applications for the ORSsurfaced in the postwar years. Some weremilitary. such as capture sights (or photo­reconnaissance planes: others civilian,such as view-finders for television camerasand cameras used in sky-diving. None.hOlNeYer, created a significant demand foroptical cak:ite. Moreover. polarizing filmreplaced calcite crystals in certain opticalinstruments, such as polarizing micro-

" CALIFORNIA GEOLOGY MARCH/APRIL 1993

scopes and devices to measure the sugarcontent of sera and other solutions(Deborah Huston. Leica. Inc.. Buffalo.oral communication. 1993). As a result.~twar domestic use of sub-optical cal­cite almost stopped. while that of trueoptical crystals dropped to or below the200-pound j90·kg}. pre-v.rar level. Newtechnologies. hovJever. have reversed thetrend and created a growing market forcakite crystals. Lasers. fiber optics. andfiber communications require the superioroptical perfonnance of calcite prisms(Vioo Vats. Carl Lambrecht Co.. Chicago.oral communication. 1992) and domesticuse now approaches 2.000 pounds(900 kg) yearly (Miller. U.S. Bureau ofMines. Washington. D.C.. oral communi­cation. 1992). Pre-war prices for crystalsranged from $10 to $20 per pound.Current prices are about $200 per poundwith a few large. perfect crystals com­manding almost $500 per pound (VinoVats. Carl Lambrecht Co.. Chicago,oral communication. 1992). There areno domestic suppliers for this market:imports are from Mexico. Brazil. India.and South Africa. Beginning with the waryears. attempts were made to grow calcitecrystals artificially (West. 1947) and todevise synthetic substitutes (Hyman.1948). As the demand and price for crys­tals has burgeoned. such efforts havebeen renewed. Until the Russians recentlysubmitted a large. usable. synthetic crys­tal. technical success was limited. Com­mercial success with substitutes is unlikely

because artificial crystals cost aOOut fourtimes as much as natural crystals (VinoVats. Carl Lambrecht Co.. Chicago. oralcommunication. 1992).

ACKNOWLEDGMENTS

Many people contributed generouslyto the research data upon which thisarticle is based. However, a special debtto Ross Whistler is gratefully acknowl­edged. Without his insatiable thirst forfacts and his ingenuity in lUlCoveringthem. the story of the OptICal Ring Sightwould be woefully incomplete.

REFERENCES

Bramlette. M M.. and Eakin, Thomas, 1943,Mines and mineral resources ot SanDiego County, California: CalilormaDIVISion 01 Mines and Geology CountyRepoJ13. p. 52.

Durrell, Cordell. 1944. Report on lhe calcitemines in northeasl San Diego County.CaMorllla In Calclle depoSIts in Imperialand san Diego counties. Calilornia'U.S. Geological Survey Open File Report77-685.31 P

Giliuly. James. 1942. Calcite depoSits neatTruckhaven. Imperial Count~. CaliforniaIn Calcite deposits In Imperial and SanOlCgO counties. Calilorllla: U.S. Geologi­cal Survey Open File RepoJ177- 685.2 p.

Hollman, Arnold. 1943. California property,interim report June 21: UOIverSlty 01Wyoming, laramie. Hotfman Collec·tlon, 4 p,

HoHman. A. 0 .. 1942. RepoJ1 on PalmWash calcite deposits. October 19:UOIverSlty 01 Wyoming. laramie.Hortman Cotlec\lOn. 6 p.

Hollman, A. D., 1944. 25th anniversaryreport 01 the Harvard UnIVersity classof 1919. p.394.

Hyman. Mark, Jr., 1948, CompoSite reSlllOUSsheet of buelringent material and methodof making the same, August 24: U.S.Patent 2,447.805. 6 p.

West, Cutler 0 .. 1947. Process of crystallormatlon, January 21. U.S. Patent2,414.679.1 p.

Wood. E.A., 1977. Crystals and light. Secondedition: Dover Publications. New York.New York. p. 147-149.

Wright. Lauren A., 1957, Calclle (opticalgrade): Minerai commoditieS of Calilor­nla. Calilornia Division ot Mines Bullelln176, p. 99-100.

Lewis Orrell is aretired ph~ical metallur­gist and bioengineer,He has taught metallurgyand bioengineering atmajor universities. Thisarticle reflects some ofthe results from a 7-yearstudy of the Optical RingSight and cakite crystalsupply.

INTERNATIONAL MARINE MINERAL SOCIETY

Meeting Qnd Coli for Popers

The 24th annual Underwater Mining Institute (UMll meeting will be held on November 7-9.1993 in Estes Park. Colorado. PresentatK>ns for tbis year's meeting are being sought for twosessions. The first will focus on how studies of marine massive sulfide deposits can benefit theexploration and development of land-based sulfide mines.

For the second session. the organizers are seeking papers concerning the exploration anddevelopment of marine minerals worldVJide.

For more infollllatlon on attending UMI and/or presenting a paper, contact,

Karynne Chong MorganUMI Conference Coordinator

811 Olomeh3n1 StreetHonolulu, Ht96813-5513

'D' (808) 522-5611FAX (808) 522-5618

CALIFORNIA GEOlOGY MARCH/APRIL 1993 "

T.:;,,,,:;.POOR.Y AEN'ORCEO CO'lCRETE-r--'h_

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Thb is one of the 9~ x 4~ CaliforniaTrol\!ek.>r guidebooks III lhe AmericanTraveler Senes Color photographs and amap of Cahlomia complement the disa.tsSlOf'I of earthquakes and faults. damageprevenlJOn. personal preparedness, andthe likelihood of earthquakes. The bookalso descnbes places 10 see faulls andeanhquake damage, and lists agenciesthat provide eanhq.,iake IIlfonnabort,

lure, tsunamis. and dam failure. In ac\di·IlOn. there is a checklist for commercialproperty eanhquake protection, a list of10pieal publicalions, and a list of resourceorganIZatIOnS.

EARTI-IQUAKE COUNTRY; Tra~<cling

Caliromia's Fault Unes, 1992. ByEJeanor t-l Ayer. Renaissance HouseN*shers, PO. Box 177. Frederick, COBOS30 (800) 521-9221 4 p_ $4 95.",h ""'"

Other books in the California seriescauer gems and minerals. birds. wUd·fkM.oers. missions. ghost tOOJrlS. parksand monuments, raIlroads, whale watching and tdal pools. day trips, historicSltes and museums. and the wine country,TIle Colorado, AriZona. and South-\\i{'S1 Traveler guidebooks COI.0" SImilarsub;ects,

,

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If tht' rt'U!-

,\-,rc",,~ <'m "'.nl/Iln1U 1< /,.... fl'lJdl/>/..."f'I /,11. ,/ ""II ''''/

I>t' /I/>k I.' ....." ,''''a,..nrl~,,, r/"'.""""'" It ,. <J",J..ro """"nrlllqulll.. 'f!l "'rh.-aJJ,tl(lfl t1f -Imfel LTp< Iwfi rrr.·w/wTr It MooI.("­NU"'i:"p firk"U",.'{fJIrC.1Ifl"1l1ll aq.rt......,/ ufT..",.,-t.·loonl.

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Earthquakes andEarthquake Safety

EffectiYe January I 1993, Cabformalaw requires sellers of mosl commercialbuildings consllUCled before 1975 10 giYethis book to l:Juyen;. The guide tughlighbcommon weaknesses soch as Iiltup waDanchorages, unremforccd masonry. andpoorly reinforced concrete It will helpo.vners, leaseholders. and potentJal buy­ers identify property weaknesses andevaluale the financial Implications ofstrenglhening them It also describesground shaking. ground failure, fault rup-

offers separate discussiQllS of volcanic,plutoniC, and metamorphic textures andmicrostructures Part ThrC(> covers pre­ferred orientations of mil'lerals In igllOOl.b

and metamorphiC rocks. 1l1ere is a Ibl ofapproximately 360 references folJou.<edby a combined glossary and Index I.\.tIlChIIllroduces the texruraltenTl poikilomo-­saic.

mE COMMERCiAL PROPERTYOWNERS GUIDE TO EARTHQUAKESAFETY 19'93, ByCalifomia'sSetsnucSafety Commission, 1900 K Street, Sowle100, Sacramenlo. CA 958144186(916) 323-4213 32 p $3 25 each fOl"up 10 fi\.le copies, soft cover

This pelrology book Is designed for aUlevels, but assune:s familiarity With thepolarizing microscope and an abibty toidentify minerals in thin section Part Onedeals With igneous and metamorphic rockclassification and leTminology, It folowsan inlemationaDy accepted hierarchy ofclaSSlfication of igneous rocks and offers asinWM sysIern for metamofphic rocks.Part Twe covers genera!lextures such astwinning, zoning. and inlergTOl.liths. lhen

This book is an introductoo to themicroscopic exalTunatlQn of rrnnerals.Besides descriptionS and systemallC ]iSb ofoptM:al properties of minerals. there aredetailed accounts of transmined light Optlcal crystallography and reflected-lightlheory, Transm1lted·light microscopyinvolves examinalion of Iransparent min­erals In thin section. while reflecled-lightmicroscopy involves examination ofopaque minerals in polished seclionTIle laller is Important to ore mineraliza­tion studies or any petrographic sludy 01rocks with high percentages of opaqueminerals,

OptICal M,neralogyand Petrology

OPTICAL MINERALOGY; Pnnciples &Practice By Colin D Gribble and Man JHal. 1992 Chapman & HaD. 29 West35th Street. New York. NY WOOl(212) 244-3336 303 p. United $tales'$4250. soft cover; $99 95. hard cauerCanada $5350. SOfl cover. $124 95.hard cauer.

IGNEOUS AND METAMORPHICROCKS UNDER THE MICROSCOPE;ClassilicalK>n, Textures. Microstructuresand Mineral Preferred Orientalions, ByDavid Shelley. 1993 Chapman & Halt.29 West 35th Street. New York, NY10001 (2IZ) 244-3336. 445 p. Umte<!Stales, $45,00; Canada. $56.50. soft

""'"

50 CAUFORNlA GEOLOOY MARCH APAI.. 1993

EARTI-IQUAKE SURVNAL GU[DIOEmergency Planning lor Family. Home.Workplace. and School By F'YarCalhoun. 1990. Magnet Press. P.O. Box3580. ""'keley. CA 94703-0580.(510) 540-0800 24 p. $1.95. soft cover.

Earthquake preparedness not onlysaves lives. but also means less personaland professional ~doum time" followinga big earthquake_This concise guidecontains information about family safety.emergency supplies. and structuralrepairs. It also addresses special p1armingfor the disabled. Survrvallaetics for post­quake concerns inducting gas leaks andfires. fallen pou.oer hnes. shelter. and con­taminated water and other sanitationproblems are covered. The guide hasappendices containing earthquake facts.earthquake insurance information. andplanning for the consequences of a bJgquake. A bibliography includes a bookabout coping VJith children's reactionsto disasters.

PEACE OF MI 0 IN EARTHQUAKECOUNTRY. By Peter I. Yanev. 1991.Chronicle Books. 275 Afth Streel. SanFrancisco. CA 94103. (800) 777-7240.218 p. $14.95. soft cover.

This book provKles the infOllT13lionand safeguards thai every resident inearthquake country should study andimplement to minimize earthquake dam­age. Although earthquakes remain fright­fully destructive and unpredictable. theireffects are highly predictable. Pre-earth­quake plannir'IQ and preparation candramaticaly mitigate the danger anddestructiveness.

The topics are grouped as follows:

• The causes and effects of earthquakes• The varying risks of different areas in

the earthquake active regions of thewesl

• The geologic and structural earth­quake hazards that every resklentshouk:I investigate

• The basic repairs and alterations toupgrade the earthquake resislance andsafety of a buikling

• The considerations that will help theproperty ()I"l,If'leT decide on earth­quake insurance

• The steps to take before. duong. aMafter an earthquake to protect familyand propeny

Peace of Mind in Earthquake Coun·try will help evaluate a house's perlormance in an earthquake It is easy tocorrect some of the most damage-pronedetails of Ilome construction. A few weakfeatures in the typkal house tend to causemost of the damage from earthquakes.particularly in older homes. Many ofthese details can easily be corrected bythe resident.

TectonICS

STRATIGRAPHY. DEPOSITIONALENVIRONMENTS. AND SEDIMEN­TARY TECfONICS OF THE WESTERMARGIN. CRETACEOUS WESTERNI"~R SEAWAY. Special Paper260. Edited by J. Dale Nations andJeffrey G. Eaton. 1991 The GedogicalSociety of Amenca. Inc.. P 0 &x9140. BoukJer. CO 80301-9140.(BOO) 472-1988. 216 p. WIth a 63-pagemicrofiche card $42.50. soft CCl'Ve'T.

This is a collectiOn of II articles onthe near-shore marine rocks that devel­oped along the western margin of theseaway during Ulte Cretaceous time.Tectonic. paleocurrent. and provenenceinterpretations shed light on the historyand development of the Sevier Thrustbelt and its foreland basin. Significantnew paleoceanographic. paleoecologic.and paleoclimatic interpretations havebeen developed on the basis of foramin­iferal and geochemical evidence.

PALEOZOIC AND EARLY MESO­ZOIC PALEOGEOGRAPHICRElATIONS: Sierra Nevada. KlamathMountains. and Related Terranes.Special Paper 255. Edited by David S.Harwood and M. Meghan Miller. 1990.The Geological Society of America. Inc..P.O. Box 9140. Bookler. CO 8030 1­9140. [BOO) 472-1988 422 p. $62.00.soft cover.

The Paleozoic aM Mesozoic meta­morphic rocks in the Klamath Mountainsand northern Sierra Nevada are now fauh­bounded blocks or terranes with uniquestratigraphk and structural hIstories.The tectonic evolution of these terraneshas been the subject of debate sincebefore the plate tectonic revoIution_ butthe debate has intensihed and broadenedin scope during the past decade. It is nowbelia'ed these rocks may be fragments

of other continentol masses that VJereMwelded~ into their present positionthrough continental collision. The pivotalquestion is whether these terranes arefar-traveled oceanic fragments unrelatedto each other and exotic to orthAmerica or \lJhether they formed alongthe active margin of North America.Related controversy exists concerningthe paleogeography of highly brokenrocks to the east in evada and frag­mented metamorphic rocks 10 the westin the Klamath-Sierra belt.

The book is a collection of 25 techni­cal papers organized chronologically intofIVe groups. from the early Paleozoic intothe early Mesozoic.

GEOLOGY OF THE POINT SUR ­LOPEZ POINT REGION. COASTRANGES. CAUFORNIA: A Part of theSouthern Califomia Allochthon. SpecialPaper 266. By Oarence A. HaD. Jr.1991. The Geological Society ofAmerica. Inc.• P.O. Box 9140. Boulder.CO 80301-9140. (BOO) 472-1988.40 p. $17.50. soft cover.

This report describes a band of rockslying west of the San Andreas Fault andeast of a group of faults including the Sur.Nacimiento. and Rinconada. which isunderlain by high--grade metamorphic andplutonic rocks and late Mesozoic sedimen­tary rocks. A reconstnxlion is based onthe structural relationships between theolder metamorphic and igneous rocks.and the overlying marine sedimentaryrocks. restoration of the rocks offset bythe San Andreas Fault System. and coun­terclockwise rotation of the TransverseRanges. This block is hypothesized 10

have been moved by the conveyer-belt­like action of obI)que subduction.

THRUST TECTONICS. Edited byK R. McClay. 1992. Chapman & Hall.29 West 351h Street. New York. NY10001 1212) 244-3336. 447 p.$149.95. hard cover.

The geologic grandeur of the Alps.the Himalayas. Pyrenees. aM the RockyMountains are all rooted in thfUS! tecton­ics. This branch of geology deals withIarge-sca1e fokls and thrust faults thatresult from compressional forces. Duringthe last decade there have been consider­able advances in the study of thrust

CAUFORNIA GEOLOGY MARCH APRil 1993 "

...more prospects

Dickinson introduces the study byproviding an updated discussion of thefollowing topics: I) pre·Laramide rockassemblages as background for consider­ing Tertiary history. 2) the nature ofkey Laramide events and their signifi­cance for later structural evolution. 3) thetiming and spacial distribution of Tertiarymagmatism. 4} the geometry 01 theCatalina detachment system and the tim­ing of tectonic unroofing of the Catalina

TECTONIC SETTING OF FAULTEDTERTIARY SmATA ASSOCIATEDWITH THE CATAUNA CORE COM­PlEX IN SOlJ1l-lERN ARIZONA. Spe­cial Paper 264. By William R. Dickinson.1991. The Geological Society ofAmerica. Inc.. P.O. Box 9140. Boulder.CO 80301-9140. 18001472-1988.106 p. $38.75. soft cover.

This Special Paper presents the stratigra·phy. sedimentology. structure, arxl tec­tonic setting of a highly extended terranenear Tucson. Arizona. The Catalina CoreComplex encompasses approximately4.000 square miles and contains the com­ponents of a classical "metamorphiccore complex." A salient characteristicof this terrane is the gently dipping

detachment fault system whichplaces cover strata against myloni­tic rocks along the flank of thecomplex.

The chapters about southern Oregonmesh well with the geology in northernCalifornia but. unfortunately. there is nocomparable California volume. This is afine piece of work and would be a wel­come edition to anyone's library.

With new mapping and observa·i';)<~~.§;;;,_ tions from key exposures.

Dickinson updates andrefines lhe stratigraphic

framework allowing for regionalcorrelation within an area characterizedby discontinuous exposures and complexstructural and stratigraphic relationships.typical of many tectonically extendedterranes. Dickinson's systematic presenta·tion and synthesis of mid-Tertiary stratafor this region help define the paleotopog'raphy which in tum provides insights andconstraints for understanding regionaltectonic models.

Fish-lIke IChthyosaurs swam elfortlesslythrough the broad shallow MesozoiC seasthat covered much o( Oregon.

The book is organized by geologic·geomorphic provlflce with a chapterdevoted to each: Blue Mountains.Klamath Mountains. Basin and Range.High Lava Plains. Deschutes-ColumbiaPlateau. Cascade Mountains. CoastRange. and Willamelte Valley. With auser friendly text. lhe focus is on tectonicsand paleoenvironments: Ihe assemblageof Oregon from foreign terranes and therelationship between tectonic plate rnoV(!­ments. volcanic actMty. earthquakes.sedimentation. and the distribution offossil plants arxl animals. There arc alsodescriptions of areas of geologic interest.a history of geologic study in Oregon.and a comprehensive bibliography.

Prior editions of this book haveachieved the status of a standard onOregon geologyarxl the current rewriteis no exception. Block diagrams arxllinedrawings are used throughout to clearlyshOVJ the story of Oregon's geologic pastNew illustrations arxl photographs areused on every page.

The volume includes a glossary arxl anindex. Reuiew by C.L Pridmore.

GEOLOGY OF OREGON. Fourth Edi­tion. By Elizabeth L. Orr. William N. Orr.and M. Baldwin. 1992. Orr Publishers.P.O. Box 5286. Eugene. OR 97405.15031345-2691. 254 p. $25.00. ",Itcover.

lhe material presented is advancedand assumes the reader has a workingknowledge of dynamic structural analysis.

One article discusses the application offault-bend fold theories to assess slip ratesalong thrust faults. Specific fold geom­etries within stratigraphic sequencesdeposited during the growth of a foldcan provide information about fault slip.Even where fault geometry is poorlyconstrained. evaluation of the associatedfold geometry can be a valuable toolfor assessing earthquake hazards. The0­retical considerations are compared Withseismic profiles from the Santa BarbaraChannel. the Los Angeles Basin. the SanJoaquin Basin. the Ventura Basin. as wellas Oklahoma. offshore Texas. thePhillipines. and Venezuela.

Thrust Tectonics will appeal tostructural geologists in industry andacademia alike. Updated tech­niques and assumptions used forbalancing cross sections and apply­ing fault-bend fold analysis aresupported by seismic data fromarourxl the world. These evoJv.ing techniques continue toprove essential for infer-ring the creation. migra-tion. and trapping ofhydnocanbons. as~1 asfor understanding thestructural and tectonicevolution of thrust terranes.

The 36 papers presented in thislIOlume cover the most recentmultidisciplinary research and theoriesof thrust tectonics in a clear. concisemanner. The articles are grouped intoseven sections covering the theoryand mechanics of thrust faulting. mcxlel­ing. geometries of thrust systemsand thrust related lokling. andfiekl-based studies of the Pyrenees.the Alps. the Himalayas. and theNorthwest American Cordillera.

systems. incOTp:)rating new fiekl observa­tions. modeling techniques. and geophysi­cal studies. This book brings together keypapers from Thrust Tectonics 1990. anintemational conference representingexpertS in the ftekl of advanced stnx:turalgeology.

52 CALIFORNIA GEOLOGY MARCH APRil 1993

core complex. and 5) alternate structuralmodels for detachment systems.

This publication woukl be of interestto anyone working in extended terranes.as well as those who have a generalinterest in tectonics and sedimentation.Because the study covers a broad area.it provides a large window into Tertiarytectonics of this region. Although thistopic has routinely been investigatedwith an emphasis on structural and meta­morphic relationships. Dickinson pro­vides a refreshing and much neededexample of how sedimentology andstratigraphy can help constrain tectonicmodels for the evolution of metamorphiccore complexes.

An accompanying color geologic map(scale: 1: 125.000) is based on compila­tion and reinterpretation of previous map­ping supplemented by Dickinson's fieklwork throughout the past decade.

Dickinson is the recipient of the 199)Geological Society of America PenroseMedal for his outstanding contributionsto the science of geology. At the Univer­sity of Arizona he continues to be inthe forefront of reconstructing regionalrelationships among sedimentation.tectonics. and magmatism. Review byC.L Pridmore.

ASSEMBUNG CAUFORNlA. By JohnMcPhee. 1993. Farrar. Straus & Giroux.Inc.. clo Putnam Publishing. P.O. Box506. East Rutherford. NJ 07073.(800) 631-8571.304 p. $21.00 plus$4.25 shipping. hard cover.

New Yorker writer John McPheecompletes his continental tetralogy."Annals of the Former Worki." with thisarmchair geologic excursion across Cali­fornia. He and various geologists follovJedInterstate 80. searching roadcuts for cluesto the global jigsaw puzzle of plate tecton­ics. He also traveled to Cypress andGreece with tectonicist Ekiridge Mooresof the University of California at Davis.McPhee explains that lhe North Ameri­can continent acquired California. pieceby piece, from far parts of the world. Henotes that the San Francisco earthquakeof 1906 was just one of tens of thousandsof great quakes that occurred dUringCalifornia's construction. His story lakesyou up the east side of the Sierra Nevada.

through the gold country. and across theGreat Central Valley to the Coast Rangesand San Francisco. where the effects ofmillions of years of geologic processescan be seen.

NEOTECTONICS OF NORTHAMERICA. Edited by D.B. Slemmons,E.R. Engdahl. M.D. Zoback. and D.O.B1adwell. 1992. The Geological Societyof America. Inc.. P.O. Box 9140. BouI·der. CO 80301-9140. (800)472·1988.508 p. $114.45 including 3 maps(1;5.000.000 scale). hard cover.

The text and maps of this volumecover three topics-seismicity. stress.and heat flow-as they relate to theNorth American continent. 1llese topicsare considered within the framework ofneotectonics. or geologic features ofNorth America dew!loped since theclose of the Miocene. about 5 millionyears ago.

Neotectonic studies have increasedat an exponential rate in recent years dueto advances in geological. paleoseismo­logical, and geophysical techniques.and to increasing population growth inseismically active. hazardous areas. Activetectonics has been described as earthmovements that are expected 10 occurwithin a time span of concern to society.

This volume of 28 artkJes. accompa­nied by three color maps. is one in theseries of the Decade of North AmericanGeology Project. Anyone interested inearthquakes. volcanoes. and other ge0­

logic hazards will enjoy it.

TECTONIC HISTORY OF THEBERING SEA AND THE EVOLlJnONOF TERTIARY STRIKE-SUP BASINSOF THE BERING SHELF. Special Paper257. By Dan M. Worrall. 1991. TheGeological Society of America. Inc"P.O. Box 9140. Boulder, CO 80301­9140. (800) 472-1988. 120 p. plus fouroversized pocket plates and eight colorplates. $42.50. soft cover.

This paper. which was developedfrom private exploration and oil companyfiles. is concerned with the broad conti­nental shelf that lies between Alaska andthe Soviet Far East. Its southern edgewas a south-facing active margin in

Cretaceous time. During the earliest Cen·ozoic. a north-facing arc·trench complexcollided and abducted this active marginfonning the mcxlern Aleutian arc-trenchto the south. Three structural episodes ofbasin fonnation lollov..red which stronglycontrol the lithology of basin strata.

The volume Is arranged into two mainparts: the first part discusses regionalgeology and the structural underpinningsof the Bering Sea: the second part coversthe evolution of the basins in the innerand outer Bering Shelf.

GraOlloid Rocks

GRANITOID ROCKS. By D.B.Clarke. 1992. Chapman & Hall.29 West 35th Street. New York. NY10001. (212) 244-3336. 283 p. $45.00plus $2.50 shipping. hard cover.

This book is a state-of-the-art sum·mary of the many volumes written ongranites and granitic intrusions. To thisend. the author presents a broad rangeof geological knowledge. as well as physi­cal. chemical. and statistical knowledgeneeded to complete a granite study.Granitoid Rocks will be useful to anyoneinvolved in the study of granitic intrusion.

Englneenng andEngineering Geology

GEon;ERMAL DIRECT USE ENGI­NEERING AND DESIGN GUIDEBOOK.Edited by Paul J. Uenau and Ben C.Lunis. 1991. Geo-Heat Center. OregonInstitute of Technology. 3201 CampusDrive. Klamath Falls. OR 97601.(503) 885-1750. 445 p.. $20.00. softcover: $25.00. hard cover: foreign post­age: $15.00. air: $3.00. surlace.

This book is a comprehensive. practi­cal reference guide for engineers anddesigners of direct heat projects. Theseprojects coukl include the conversion ofgeothermal energy into space heatingand cooling of buildings. district heating.greenhouse heating. aquaculture. andindustrial processing. lbe book also cov­ers the nature and exploration of geother­mal resources. drilling. and completionof geothennal wells through well-testingand reservoir evaluation. Engineers anddevelopers will find technical informationon low- and moderate-temperature

CALIFORNIA GEOLOGY MAACH,APAIL 1993 "

· ..and more prospects

(100"· 300') geothermal applications andequipment.

This revised version of the guidebookwas prepared for the U.S. Depanmentof Energy. It represents a two-year coop­erative effon by the Oregon Instituteof Technology. Idaho National Engineer­ing Laboratory. University of UtahResearch Institute. Battelle Pacific NW.Laboratories, Radian Corporation, andWashington State Energy Office.

ENGINEERING UNrr CONVERSIONS.Second edition. 1990. By Michael R.Undeburg. Professional Publications. [nc..1250 Fifth Avenue. Depanment55.Belmont. CA 94002. (415) 593-9119.160 p. $19.95 plus $3.75 shipping.hard cover.

Engineers use Wlits common to math­ematics. physics. chemistry. and construc·tion Irades. This book was wrillen 10assist readers in converting familiar unitsto those used in other disciplines or coun­tries and vice versa. It eliminates the needto develop compound Wlit conversions(e.g.. gram-ealorie-centimeters per squarecentimeter-second-c\egree centigrade toBTU-feet per square foot-nour-c\egreeFahrenheit) from basic units. Conversionsin the first edition have been reviewed foraccuracy and hundreds more added. [nthis second edition. more than 4.500conversions cover traditional English.conventional metric, and SI units in thefields of civil. mechanicaL electrical. andchemical engineering.

ENGINEERING GEOLOGY; Rock inEngineering Construction. By RichardE. Goodman. 1993. John Wiley andSons. Inc.. 1 Wiley Drive. Somerset. NJ08875-1272. (800) 225-5945. 412 p.$70.95. hard cover.

This textbook is geared to theadvanced undergraduate or graduate

student. It introduces geology (especiallythe properties and behavior of rocks) tofuture civil engineers. It focuses on theexperience record of different types ofrocks in the construction of civil engineer­ing works. Most interesting is the discus­sion of rocks that tend to pose specialproblems because they are weak, blocky.alterable. highly soluble. or pervious.

Case histories are used throughout toemphasize construction site experiences.Sources of Information are listed at theend of each chapter.

THE HERrrAGE OF ENGINEERINGGEOLOGY; THE ARST HUNDREDYEARS. Centennial Special Volume 3.Edited by George A. Kiersch. 1991.The Geological Society of America, [nc._P.O. Box 9140. Boulder. CO 80301­9140.18001472-1988.605 p $62.50.hard cover.

This compendium reviews thechanges in engineering geology Ihrough­out history.The rationale for the sub;ectsof history. geologic processes. naturalmaterials, investigations for engineeringworks. and the geologists' responsibilitiesin litigation are covered in 25 ankles byexperts in each fiekl. The articles alsodetail the reaction of works to the ge0­

logic environs including early dam con·struction. seismotectonic research. andlandmark litigation decisions involvinglandslide damage to buildings.

ForenSIc Geology and Engineering

FORENSIC GEOLOGY. By Raymond C.Murray and John C.F. Tedrow. 1992.Order Processing Center. Prentice-Hall.Inc.. P.O. Box 11073. Des Moines. [A50381-1073. (515) 284-6751. 203 p ..$56.00. hard cover.

The authors address three separateand diverse audiences. The first includesforensic scientists, attorneys. and lawenforcement offkers. To these profes­sionals the book conveys the basic lan·guage of gooIogy and soil science and theideas that should be applicable to theirparticular problems. The second audiencecomprises professional geologists. Thebook applies geology to criminology andshoVJS the geologists hoo.v their l.\.'Ofk maybe used for forensic problems. Making upthe third group are practicing forensicgeologists who want to expand theirknowledge of types of problems and ge0­

logical methods used to solve them.

Many sample cases are cited in thelext and are used to illustrate particularlegal points. Forensic Geology containsinput from many agencies including theFederal Bureau of Investigation, stale andlocal police depanments, and geologicalconsulting firms. The book may have its

greatest value in serving the needs ofthe non-geologist who requires summaryinformation on geologic methods andprocedures.

FORENSIC ENGINEERING. By GerardShuirman and James E. Slasson.1992. Academic Press. [nc.• 6277Sea Harbor Drive. Orlando. FL 32887.(800) 321-506.3. 296 p. $49.95. hardcover.

Increasingly. architects. engineers.geologists. and landscape architects arecalled upon to be expert witnesses in liabil­ity suits resulting from flood. erosion. land­slide. muds/ide, or other type of naturalhazard-related damage. They may have todefend their actions or those of their orga­nization. Or. they may act as independentexpens for individuals and their attorneyswho are bringing suits or defending them·selves against such suits. Forensic Engi·neering will be of great value to expenwitnesses. It explains the needs of anexpen. the relationship of the expen tothe client and to the attorney. and thecha[1enges that may be faced.

The first chapter gives a concise butthorough summary of duties an expenmay have in trial work. duties which areunusual to most with technical trainingand experience. The bulk of the volumedeals with case histories involving Iand­sliding. flocxiing. land subsidence. andstream morphology. Each case has beenchosen because it illustrates a number ofgeologic and \egal problems. The finalchapter is a discussion of ethics for thescientist considering work as an expertwitness. The reference list is not exhaus­tive but includes many basic papers inboth forensic geology and legal decisions.

Relerence

EARTH SCIENCES REFERENCE.By Mary McNeil. 1991. Flamingo Press.2958 State Street. Carlsbad. CA 92008.709 p. $55.00 plus $5.00 shipping. hardoove<.

This is an introductory research toolcovering ecology. energy. environment.geography, oceanography, meteorology.and mineralogy. Middle-school students aswell as adults will find it readable. Entriesare alphabetized and cross referenced.The volume has an extensive bibliography.a geographical index. and a general index.

CALIFORNIA GEOLOGY MAACH,,\PRll1993

TeacherFeature

THE GEOLOGICAL SOCIE1Y OF AMERICAScience Awareness through Geoscience Education

SAGE

The SAGE program represents TheGeological Society of America's (GSA)commitment to improving earth scienceeducation and enhancing scientific under­standing lor all citizens. SAGE includeseducational initiatives in the areas ofpartnering, teacher preparation andenhancement, women and ethnic minor­ities. leacher and student awards. edu­cation materials development, networking.and information dissemination.

EDUCATION INITIATIVES

Partners tor Excellence:Teachers + Students + Scientists

Partners for Excellence is a programdeveloped by SAGE to bring togetherleachers. students. and earth scientists andhelp them fann creative and mutuallybeneficial educational partnerships. SAGEpartnerships offer teachers and studentsthe opportunity to gain relevant. up-to-dateknowledge about diverse earth sciencetopics. while at the same time givingearth scientists opportunittes to contribute10 and Ieam about the precollege sdenceeducation system. Pannering acfkiitiesinclu:le dassroom presentations. laboratOfydemonstrations. fidei trips. and mentor·ing. Partnering often inYoIves groups ofscientists. teachers. and students workingtogether, or one"'Ofl'OOe sessionS beNleenthe scientist and teacher or between thescientist and student. Participants in thisprogram are encouraged to develop thetype 01 partner.ihip that best matches theirunique needs, interests. and skills. GSAsupports all Partners for Excellence byproviding training. materials. and foUoorupsupport.

WOMEN AND ETHNIC MINORITIES INTHE EARTH SCIENCES

One oJ GSA's top educational prioritiesis to encourage women and ethnic minori­ties to pursue careers in science and engi­neering. In conjunction with GSA's Womenand Minorities Commillee. the SAGE pro­gram is working toward this goal by involv-­ing women and minority scientists in thePartnering program. Professional scientistsand graduate students are encouraged tomentor individual students. and sponsorteachers and students so they may allendGSA's Annual Meeting

AWARDS FOR TEACHERS ANDSTUDENTS

To encourage and acknowledge excel­lence in precollege earth science teaching,the SAGE program recognizes OlD' nation'soutstanding earth science teachers ulith$1.000.00 awards. These teachers areselected from across the COUltry by theNational Association 01 Geology Teachers.Recipients may use their awards to attendGSA meetings, purchase materials for theirearth science classrooms. or help createnew earth science activities and curricula.

GSA also encOUJageS student earthscience research by av.'aJliing grants 10

graduate students for original projects in thelaboratory and the fieki.

COLLECTING AND DISSEMINATINGINFORMATION

GSA pnxloces high-quality earth sciencebooks, periodicals. field guidebooks. maps.videos. and posters for earth scientists andteachers. The SAGE program will expandthis resource base so it can beller accommo­date precollege science teachers and stu­dents. This will be accomplished through amulti-organizational Earth Science Informa·tion Clearinghouse and the development ofvkieos and brochures. For more informationon 5.t\GE programs. contact,

Or. Edward E. GearyCoordinator for Educational Programs

The Geological Society of AmericaP.O. Box 9140

Boulder, CO 80301-91401f (303) 447-2020 or (800) 472,1988

FAX (303) 447-1133

InlotmlllO:ln lltI<ton 110m E.m s.:.en.:. E_fIOIl~199,·20(}1 nw~SocofIyol~

Dinah Shumway. DMGgeologist working onmineral land classltica­tion project in the Cali·fornia desert. Photo oyCindy Pn(}more.

CALIFORNIA GEOLOOY MARCH/APRIL 1993 55

DMG Open-FUe Report Releases IReference copies of the OFRs listed

here aTe aooilable at aI/three DMGoffices. in addition. they are oooilablefor prepaid moil order from the Sacra·menta office. Over·the-counter salesQuailability differs with each OFR. andis indicated immediately following itsrelease annoullcement.

DMG OFR 92-09 MINERAL LANDCLASSIRCAnON OF THE BOULDERCREEK AGGREGATE SITE. FlLU\10REQUADRANGLE. VENTURA COUNTY.CAUFORNIA FOR PORTLANDCEMENT CONCRETE. ASPHALTICCONCRETE AGGREGRATE. ANDBASE AGGREGATE. By Rudolph G.Strand. 1992. $5.00.

In response to a petition. the SouthernPacific Milling Company Boulder CreekSHe. covering approximately 553 acres ofland within the Fillmore 7.5-minule quad­rangle. Ventura County. was classified forportland cement concrete. asphaltic con­crete aggregate. and base aggregate. Amajority of the property is classified MRZ­2a, areas of identified significant mineralresources. A small portion of the propertyis classilied MRZ-4. areas of no knownmineral occurrence. The property consistsof contiguous parcels of land in Sections27.28. and 34 of Township 4 North.Range 20 West. San Bernardino Base andMeridian.

Over·the·counter sales are availab1e at theSan Francisco and Sacramento offices.

DMG OFR 92-07 RECENTLY ACIlVETRACES OF THE RODGERS CREEKFAULT. SONOMA COUNTY. CAUFOR·NIA. By Earl W. Hart. 1992. $8.00.

OFR 92-07 identifies re<:ently activetraces of the Rodgers Creek Fault. anactive member of the San Andreas FaultSystem. The traces are shown on anannotated map (scale: 1:24.000). whichdocuments the evidence for re<:ency. Italso identifies associated landslide andlateral-spread features that may be acti­vated during a major earthquake. Therepon should be of interest to geoscientistsand planners.

Over-the-counter sales are available at theSacramento and San Francisco oflices.

DMG OFR 92-05 LA.NDSUDE HAZ­ARDS IN THE TASSAJARA ANDBYRON HOT SPRINGS 7 1/2' QUAD­RANGl£S. ALAMEDA AND CONmACOSTA COUNllES. CALIFORNIA.By Hasmukhrai H. Majmundar. 1991.3 plates. Scale: 1:24.000. $7.00.

This set of three maps constitutesLandslide Identification Map 1127. Themaps provide infonnation about slopestability for use boy local officials for land·use planning and evaluation of building­permit applications.

The study area covers about 15square miles of mostly undeveloped.landslide-prone. grass-covered hill countrywith few oak-studded rounded hills andforested mountains {Black Hills)_ Thearea is dissected boy Hog. Curry. Rigs.Doolan. and Collier canyons and thevalleys along Marsh. Sycamore.Tassajara. Cayetano. Kellogg. and Brushycreeks. The mapped area lies aboul50 miles east-southeast of San Franciscoand the Alamc<ia/Contra Costa countyboundary crosses its southern portion.Although only two small towns. Bryonand Byron Hot Springs. lie within thearea. it abuts the rapidly developing areasof Livermore. Danville. Dublin. SanRamon. Blackhawk. Alamo. Clayton.Antioch. and Brentwood. Access to theregion is via Interstate 680 on the westand Interstate 580 on the south.

Over·the·counter sales are available at theSan Francisco and Sacramento offices_

DMG OFR 90-19LANDSUDE HAZ­ARDS IN THE NORTH HALF OF THEBLACK STAR CANYON QUAD­RANGLE. ORANGE AND RIVERSIDECOUNTIES. CALIFORNIA. 3 plates.Scale: 1: 12.000. By Siang S. Tan. 1992.$8.00.

This set of three maps constitutesLandslide Hazard Identification MapNo. 17. The maps provide infolTIlationabout slope stability lor use boy local

officials in land-use planning and evalua­tion of building-permit applications.

The study area is approximately15 miles northeast of downtown SantaAna and 35 miles southeast of dovmtownLos Angeles, in northeastern OrangeCounty and westem Riverside County.It lies within the northwestemmost part01 the Santa Ana Mountains in the Penin­sular Ranges geomorphic province ofsouthem Califomia, and covers about30 square miles. Terrain ranges fromthe nearly level floodplain of the SantaAna River on the nonh to the steep andrugged Santa Ana Mountains on thesouth. Access to the eastem pan is pro­vided boy a network of unpaved fire andranch roads. On the west. paved cityroads provide access south of State High­way 91 that crosses the northem part ofthe area. Current land use. outside of theCleveland National Forest. includes cattlegrazing. sand and gravel mining. andre<:ent residential development in Ana­heim on the nonhwest and Corona onthe northeast.

Over-the·counter sales are available at theLos Angeles and Sacramento otlices.

DMG OFR 92-02 MINERAL LANDCLASSIFICAnON OF THE WINCHES­TER AGGREGATE SITE. ROMOLANDAND WINCHESTER QUADRANG1£S.RIVERSIDE COUNTY. CAUFORNIAFOR ASPHALTle-CONCRETE-GRADEAGGREGATE AND BASE-GRADEAGGREGATE. By Rudolph G. Strand.$5.00.

In response to a petition. theCrestmore Materials Company Winches­ter Site. covering approximately 155acres of land within the Romoland andWinchester 7.5-minute quadrangles.Riverside County. was classified forasphaltic-concrete-grade aggregate andbase-grade aggregate. Part of the prop­erty is classified MRZ-2a. areas of identi­fied significant mineral resources: panis classified MRZ-3a. areas of undeter­mined mineral resource signifiance: andpart is classified MRZ-4. areas of noknown mineral occurrence. The propertyconsists of the Southeast 1/4 Section 19.Township 5 South. Range 2 West. SanBernardino Base and Meridian.

Over-the'counter sales are available altheSacramento ollice.

CALIFORNIA GEOLOGY MARCH APRIL 1993

_____STATE Z,p _

AMOUNT ENCLOSED (Price includes postage and sales lax.) $

A CHECK OR MONEY ORDER MUST ACCOMPANY THIS ORDER. All non·U 5 orders muSI be paidWith an InternatIOnal money Ofdel' Of dral1 payab~ In US (loIlals and made out to DIVISION OF MINESAND GEOLOGY send Ofdel' to DIVISION OF MINES AND GEOLOGY. P 0 80x 2980. Sacramento.Ca~tornia 95812·2980

NAME

STREET

... Free

... $2.00

........................................ $7.00........................................... $7.00.......................................... $7.00........................................ $7.00

The map shows the general geologicframework of the area and provides basicgeologic infonnation on the age. distribu­tion. and description of the rocks. locationof fault and other geologic structures. Thearea is underlain primarily by Neogenevolcanic rocks that OV€r1ie an older and forthe mosl part concealed basement. con­sisting 01 Cretaceous and pre-Cretaceousgranitic and metamorphic rocks. Base­ment rocks are exposed in an uplifted.fault-bounded block in the Gallatin Peakarea. southeast of Eagle Lake in thesouthwest quarter of the map. The bulk ofthe rock units within the map are Mioceneto Pliocene-aged volcanic rocks of rhyoliticto basaltic composition. These rocks occur

metric base at a scale 011:100.000(l inch equals about 1.6 miles).

SPECIAL PUBLICATIONS

SP074 Mineral commodity report· sulphur. 1984 55.00SP075 Minerai commoclJty report - zeolites. 1984 $5.00SP076 Mineral commodity report - barite. 1985 $5.00spon Minerai commodity report - magnesium compounds. 1985.... ._. $5.00SP079 Mineral commodity repol1 - anhydrous ammonia (mlrogen). 1985 $5.00SP080 Mineral commodity report - calcium chloride. 1985 $5.00SP081 Mineral commodity report - sodium sulfate. 1985 $5.00SP082 Mineral commodity report - salt. t985 55.00SP083 Minerai commodity report - sodIum carbonate. 1985 55.00SP084 Mineral commodity report - phosphate rock. 1985... . 55.00SP089 Mineral commodity report - slhca. 1986 55.00SP090 Mineral commodity report - talc and related minerals. t 986 .. ... 55.00SP111 Minerai commodity report - diatomite. 1991 .. . $6.00

CALIFORNIA GEOLOGY

Back Issue (specify volume and month) . . .

OTHERList ot Available Publications .

"The map area includes part of theModoc Plateau and Basin and Rangegeomorphic provinces of northeasternCalifornia and covers approximately1.850 square miles of east-centralLassenCounty.

DMG OFR 92-14 has a geologic mapplate and explanation explaining geologicunits. map symbols. references. andsources of data used in the compllation.The geologic map is compiled on a plani-

reconnaissance geologic maps were avail­able for this area. The report was pro­duced by the Division of Mines andGeology's Regional Geologic MappingPro)ecl. Reid VJOrk was supported in partby tile U.S. Geological Survey Coopera­tive Geologic Mapping Program.

-----------------------~----i DIVISION OF MINES AND GEOLOGYI Publications Request Form

Number 0' copI9S

I AEROMAGNETIC MAP (Ic.le; 1:250.000)

I __AMM005 San FrancIsco-san Jose quadrangle. 1993 (NEW) sa.OOGEOLOGIC ATLAS OF CALlFQflNIA (reprlnts) (1(:818: 1:250.000)

GAM007 Long Beach Sheet. 1962 .GAM019 Santa Ana Sheet. 1965 .GAM020 Santa Cruz Sheet. 1959 .GAM026 Walker Lake Sheel. 1963 .

Over-the-counter sales are available at thesan Francisco and Sacramento oHices.

This report presents the results ofDMG's mineral land classification study ofTeichert Aggregates' South Tracy site inresponse to a petition submitted underthe provisions of SMARA. This study is are-evaluation of the portland cement con­crete aggregate potential of the 325-acreSouth Tracy site. between Hospital andLone Tree creeks in southwestern SanJoaquin County.

DMG OFR 92-14 makes existinggeologic data for the Eagle Lake 30 x 60minute quadrangle available to the public.Prior to its release. only unpublished

DMG OFR 91-03 MINERAL lANDCLASSIACATION OF THE SOlffi-lTRACY Sill:. SAN JOAQUINCOU!'fIY. CAUFORNIA . FOR PORT·LAND CEMENT CONCRETE AGGRE­GATE. By Richard Eh;Ian and RalphLoyd. 1991. $6.00.

Over-the-counter sales are available at theSacramento and san Francisco oHices.

DMG OFR 91·05 LANDSUDES ANDOTHER GEOLOGIC FEATURES INTHE SANTA CRUZ MOUNTAINS.CAUFORNIA. RESULTING FROM THELOMA PRIETA EARTHQUAKE OFOCTOBER 17. 1989. Compiled byMichael W. Manson. David K. Keefer.and Mary Anne McKittrick. 16 plates.Scale: 1:48.000. 1991. $12.00.

DMG OFR 92-14 GEOLOGIC MAPOF TJ-IE EAGLE LAKE QUADRANGLE.LASSEN COU!'ITY, CAUFORNIA.By T.L.T. Grose. G.J. Saucedo. andD.L. Wagner. 1992. $8.00.

This set of maps depicts nearly 500numbered localities where earthquake·induced landslides. or other surface effectsof the Oclober 17. 1989 Lorna Prietaearthquake were observed by geologists.building inspectors. and other contribu­tors. 1he text consisls of annotations foreach locality that describe earthquake­triggered geologic features such as rockfalls. rock slides. soil slides. s1wnps orblock slides (in natural or fill materials):liquefoction effects Oateral spreading.settlement. saOO boils); and ground cracksor fissures.

CALIFORNIA GEOLOGY MARCH APRIL 1993 57

CITY STATE ZlP _

STREET _

NAME (Please print or type) _

29th FORUMON THE GEOLOGY OF

INDUSTRIAL MINERALSSponsored by

The California Department01 Conservation

DIVISION OF MINES AND GEOLOGYand THE U.S. BUREAU OF M!NES

Aplil 25·30. 1993

Long Beach. California

ADDRESSES OF DMG OFFICES

Publications and Information Office801 K Street, MS 14-33

Sacramento. CA 95814-3532(916) 445-5716

Southern California Regional Office107 South Broadway. Room 1065

Los Angeles, CA 90012(213)620-3560

Bay Area Regional Office1145 Market Street. 3rd Floor

San Francisco. CA 94103·1513(415) 557·1500

The 29th Forum will emphasizeindustrial mineral deposits of the south·em Califomia region and will include2 days of technical sessions and 3 daysof fiekl tlips.

Registration: Participant registration(banquet included) - $125Late registration (after March 31.1993) (banquet included)- $150Spouse registration (banquetincluded)- $50

Tuesday Field Trips: $45 pertrip. 111 Lompoc Diatomite:112 Irwindale Aggregate {CaIMatCompany)lLuceme Valley Limesfone: 113 Irwindale Aggregate{Livingston-Graham. Inc.)lSoledadCanyon Ilmenite

Thursday-Friday Field Trips:$100 per tlip. 114 Mojave DesertBorate/Brines/Hectolite:115 Mojave Desert Hectolife/BorateIBrines

For more infonnation, contact:Ralph Loyd29th Forum

801 K Street. MS 08-38Sacramento. CA 9S6'4-'353'

1r (916) 322·9207 FAX (916) 327·1853

3 yrs. $28.00(18 issues)D

GEOLOGIC ATlAS OF CAUFORNlAReprints Available(scale: 1:250,000)

Long Beach Sheet. 1993. Compiled byCharles W. Jennings. 1962 $7.00

Santa Ana Sheet. 1993. Compiled byThomas H. Rodgers. 1965 $7.00

Santa Cruz Sheet. 1993. Compiled byCharles W. Jennings and Rudolph G.Strand. 1959 ... $7.00

Walker Lake Sheet. 1993. Compiled byJamesB. Koenig. 1963 $7.00

AEROMAGNETIC MAP RELEASE(scale 1:250.000)

The Aeromagnetic Map of the SanFrancisco-San Jose Quadrangle is avail·able for $8.00.

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The follOl.ving maps may be orderedon the Publications Request Fonn onpage 57.

primarily as flows but include pyroclasticdeposits. breccias. and vent facies thatoriginated from local mountain peaks asv..rell as from sources outside the maparea. The intelV€ning lowlying areas areunderlain by alluvial. fluvial. and lacustrinedeposits as well as younger volcanic flows.Faults offset most of the units in the area.Generally. they are north to northwesttrending nonnal faults with down to thewest displacements. In many cases, how­ever. east dipping nonnal faults combineto create basin and range type structures.

Over the counter sales are available at theSacramento and San Francisco offices.

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Allow 60 days to rellect address change. IA CHECK OR MONEY ORDER MUST ACCOMPANY THIS ORDER. All non·U S orders must be paid Iwah an rrllemallOnaJmoneyordero.dra!lpayable.n U_S dollars and made oullO DIVISION OF MINESAND GEOLOGY send all orders and/or address change to: I

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58 CALIFORNIA GEOLOGY MARCH/APRIL 1993

PREI1MINARY REVIEW MAPS OFPROPOSED SPECIAL SnJDlES ZONES OF JANUARY 1. 1993

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Preliminary Review Maps issued January I.1993 (map numbers keyed 10 index map)

1. Mark Wasl Spnngs2. M1. George3. Cordelia4. Fairfield South5. Vine HIli (formerly Port ChICago)6. Walnut Creek7. Clayton8. Landers9. Yucx:a Valley North

" O. Yucca Valley South11. Joshua Tree South

• Rel'lSed ZonB map

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Counties

Contra CostaRiversideSan BernardinoSolanoSonoma

Cities

BeniciaConcordFairfieldWalnut CreekYucca Valley

PROPOSED WITHDRAWALOF SPECIAL STUDIES

ZONES MAPS

CilleS and coumies affectedby proposed new or proposedSpecial Sludies Zones shov.mon preliminary Revicw Mapsof January I. 1993;

The lwO Olfici<ll SpecialStudies Zones Maps listed belowaTe proposed for withdrawalfollowing the same schedule as.""'"

A. AntIoch NorthB. Antioch South

1lle propos«! new and revised Special Studies Zones Maps are issued for review purposes pursuant to tne Alqwsl Priolo Spe<:ial Studies Zones ActFollowing a review perkxl thai ends April I. 1993. they ...;11 be superseded by OffICial Maps on July 1. 1993. I'It which time the roning beeorrM.':SeffectiYe

Review copies of the Preliminary Review Maps are in the offices oltne affected Cities and counties and the DMG olliceslisled above. Copies llllIybe purchased from Blue Print SelVice Company. 1147 Mission Streel. San Frot'ICisco. CA 94103. (415) 512-6550

For infonTlatlon on Officiol Mops of Special Studies Zones previously issued. and lor provisions of tne l\Iquist·PrioIo Special Studies Zones Act. seeDMG Special Publication 42. Fault-rupture Hazard Zones in Califomia 11 Is ovaiiable from DMG. PO Box 2980. Sacramento. CA 95814. orfrom the offices listed aboYe. lor $3 00.

PUblICatIons and InlormabOn 0II1Ce80t K Streel. MS 14·33

Sacramenlo. CA 958t4·3532(916)445·5716

Bay Area RegIonal 0It1Ce1145 M,lIket Slreet, 3rd Floor

San Franosco. CA 94103·1513l415l557·1500

Southern Calrlorma Regional OffICe107 South Broadway. Room 1065

los Angele$. CA 90012(213)612-3560

CAlIFQflNIA GEOlOGY MARCH.APRlll993 "