ORIGINAL ARTICLE

The Etruscan BVolumni Hypogeum^ Archeo-Geosite: NewSedimentological and Geomorphological Insights on the TombalComplex

Laura Melelli1 & Roberto Bizzarri1 & Angela Baldanza1 & Lucilia Gregori1

Received: 22 August 2014 /Accepted: 28 October 2015 /Published online: 5 November 2015# The European Association for Conservation of the Geological Heritage 2015

Keywords Geoarchaeology . Geosite . Etruscan hypogeum .

Umbria . Italy

Introduction

Geoarchaeology is a multidisciplinary field that uses themethods and the contents of Earth Sciences for a more com-plete and detailed investigation of historical sites (Waters1992; Rapp and Hill 1998; Goldberg and Macphail 2005;Ghilardi and Desruelles 2009). In particular, thegeoarchaeologycal investigation of a site focuses on the studyof stratigraphic sequences and on the clear understanding ofthe geomorphological and palaeogeographic setting of the ar-ea. One of the main goals is to better recognize the ancientenvironmental context in which the settlement wasestablished. This approach is rather recent, given that the sys-tematic stratigraphic analysis of excavation sites has beenused only since the end of the nineteenth century, while thegeomorphological reconstruction of the palaeogeographic en-vironment has been applied only since the 1980s (Ghilardi andDesruelles 2009). Moreover, important information is obtain-ed from the study of environmental changes occurred from theperiod during which the settlement was established until now-adays. Since the location of a historical place is strictly relatedto the geographica l condi t ions of the s i t e , thepalaeogeographic study is essential to localize the positionof a site or to understand its time evolution.

In this context, the use of geographical information systems(GIS) technology plays an important role, allowing for theinvestigation of natural and/or artificial characteristics of theEarth surface (Moore et al. 1991; Nelson et al. 2009; Melelliet al. 2012). The great flexibility of these techniques allows usto compare and integrate data provided by Social Sciences aswell as Sciences, thus providing unique indications forGeoarchaeology.

Until now the integration of Earth Sciences andArchaeology has been mainly used for archaeological pur-poses. Indeed, Earth Sciences have been used as a Btool^ forarchaeological research, with a few feedbacks or advantagesfor the geological field. On the contrary, now, new potentialconnections are emerging, with the development of newbranches of the Earth Sciences, including the geological her-itage identification and promotion. Geological outcrops andgeomorphological features characterized by intrinsic, cultural,economic, scientific and educational values are defined in thescientific literature as Bgeosites^ (Panizza and Piacente 2008).These geological heritages are defined as Bany place, area orterritory where you can define a geological and geomorpho-logical interest for conservation^ (Grey 2004); in addition tothe abiotic values, they can have a strong historical, archaeo-logical and cultural relevance (Melelli 2014; Pica et al. 2015).

In order to promote the geological heritage with culturaladded values, some archaeological sites, where the strati-graphic or geomorphological surrounding conditions are rele-vant, can be defined as Barchaeo–geosite^ (Gregori et al.2005; Gustavsson et al. 2006; Güngör et al. 2012).

Moreover, this new approach for the investigation of anarchaeological site allows us to export its value from the aca-demic context to a more wide audience, thus increasing itstouristic value, and consequently, the economic value of thearea. Accordingly, geotourism (a particular branch of tourisminterested in the knowledge of the geological heritage) is the

* Laura Melellilaura.melelli@unipg.it

1 University of Perugia, Perugia, Italy

Geoheritage (2016) 8:301–314DOI 10.1007/s12371-015-0162-z

best approach to promote these areas (Dowling and Newsome2006; Asrat and Zwoliński 2012; Gordon 2012). In order tohighlight the geologic component of an archaeological site,research methods have to be rigorous and scientifically valid.In addition, they must be easily communicated to the touristiccomponent. The dissemination of results has to be directlyaccessible on the site, through exhibition panels or audio-videos, which must provide the basic geological informationin an understandable and scientifically valid manner. By usingthis approach, the aspects related to Earth Sciences have to bemerged in synergy with Archaeology to give a new impulsefor the scientific and the economic development of an area.

The case study presented in this paper focuses on an un-derground Etruscan tomb. The Etruscan Volumni Hypogeum,located in Perugia (Umbria, central Italy), is proposed as anexample of archaeo–geosite. This kind of burial is a methodcommon to many civilizations. From a geoarchaeologicalpoint of view, this burial practise provides a unique opportu-nity to have a 3D view of geological outcrops. The tomb iswide and articulated in different rooms, and there are no paint-ings covering the walls. Therefore, the perimeter walls allowfor the observation of the spatial patterns of many geologicalstructures. Moreover, given the underground location of thetomb, the bedrock is well preserved because it was not sub-jected to strong physical or chemical weathering.Consequently, outcrop characteristics are in excellent condi-tions providing the opportunity for detailed geologicalinvestigations.

The present work also describes a procedure to show howan archaeological site can be enhanced for both scientific pur-poses and for the management of the site.

We suggest a new method, which is applicable to differentarchaeological sites, to promote an essential cooperation be-tween Earth and Social Sciences for the recognition and pro-motion of archeo-geosites.

Etruscan History of Perugia, Gravesand the BVolumni Hypogeum^

The Etruscan civilization started in the first millennium B.C.in an area of central Italy named Etruria (Haynes 2000). Thefirst Etruscan inscriptions have been dated to the eighth cen-tury B.C. Although Etruscan population had a single languageand a religion, the society was organized in a network ofindependent cities. During the period of maximum expansion,the Etruscan civilization was present from the Po river valley,in Northern Italy, to the Campania region in Southern Italy((Fig. 1) Barker and Rasmussen 1998; Vernesi et al. 2004).The expansion of the Roman Empire and the weak militaryorganization of Etruscans caused the decline of Etruscan cities(90–89 B.C.).

Although it was an Umbrian settlement, Perugia reached astrategic role only since the Etruscan period, when it was oneof the 12 confederate cities of the Etruria league (Perusia inFig. 1). Its position on the top of a hill above the Tiber Rivervalley allowed Perugia to become a strategic point for eco-nomic trades with the other cities. During the expansion of theRoman Empire, unlike other Etruscan towns, Perugia main-tained its role and importance until the first century B.C.,when the bellum Perusinum (Perugia war) ratified the defini-tive submission of Perugia to Rome.

The city boasts numerous finds of the Etruscan presence,including city walls and artefacts and several necropolis (Natiand Nardelli 2010) that offer considerable evidence of a sig-nificant economic advance occurred since the sixth centuryB.C. Starting from the second century B.C., an important pop-ulation growth occurred. In this period, higher social classesstarted building important and magnificent graves. The re-markable necropolis of Palazzone, including the VolumniHypogeum, was built in this historical context (Fig. 2).

The funerary architecture plays a key role in Etruscan cul-ture because of the belief that life continued beyond death. Forthis reason, graves were built to ensure durability and futureexpansions. Graves were built in stone or carved into coherentlithotypes. Like many other ancient peoples, the Etruscans hidtheir graves by locating them underground or covering themwith soil. In order to represent the idea of life, tombs weregrouped in necropolises (cities of dead people). Necropoliseswere placed outside the city walls and differently located de-pending on the local topographic conditions.

The main types of Etruscan tombs are: tumulus, aediculaand hypogeum. The tumulus graves are only partially buried.They can be rectangular or circular. Access is granted by anopen door located in the front, followed by steps or by adownhill ramp and by a corridor (dromos). The rest of thebuilding, made of stone blocks, is completely covered by ahill-shaped mound of earth. The aedicula graves have theshape of rectangular little houses, with a single room. Theyare completely exposed above ground. The hypogeum gravesare built completely underground, dug into the substrate orusing natural caves. These graves consist of steep access steps(dromos) leading directly into an entrance hall. Here, usually,six graves are present, reached by narrow corridors. This kindof graves was reserved only for people having a high socialstatus, especially politicians, soldiers and priests. On the walls,rock beds or benches may be present, where the remains andfunerary furnishings were placed. The walls, doors and ceil-ings may be carved in various ways. The ceiling could imitatereal wood ceilings, with a central beam (columen) embossedwith its rafters (cantherii) on sloping. Columns with capitals,chairs, stools, cornices, doors, windows, shields, carved anddecorated beds and pillows may be present.

The Volumni Hypogeum, one of the most importantEtruscan hypogean graves in central Italy, is located

302 Geoheritage (2016) 8:301–314

Fig. 1 Etruscan domination areas. (1) Etrutria, 750 BC. (2) Etruscan expansion, 750–500 BC. (3) Etruscan League city. Perusia is the Etruscandenomination of Perugia. On the top of the figure, the location map with Umbria region and Perugia location

Fig. 2 To the left: the Palazzone necropolis plan. (1)VolumniHypogeum.(2) Tombs. (3) Present buildings. (4) Contour lines (5 m interval). To theright: the Volumni Hypogeum plan. Arabic numbers are referred to

different rooms (from 1 to 10). The walls in each room are indicatedwith letters (from A to E), the walls along the entrance hall with romannumbers (from I to VIII). The order is clockwise

Geoheritage (2016) 8:301–314 303

approximately 4 km from the acropolis (central and most ele-vated part) of the town of Perugia and along the south-easternmargin of the hill (Fig. 2). The Necropolis of Palazzone, in-cluding the Hypogeum, consists of almost 200 hypogeantombs related to the Hellenistic and only partially to theArchaic Age. The first archaeological study was carried outin 1840 and, subsequently, the necropolis has been studiedfrom 1963 until today. All the tombs are of the chamber type,preceded by a small dromos.

The Volumni Hypogeum, dated to the second half of thesecond century B.C., belonged to the Velimna family (Volumniin Latin), whose brothers founded the tomb, as witnessed bythe inscriptions on the cinerary urns and on the doorjamb atthe entrance. The tomb, now easily accessible by a modernstair, is entirely dug into the ground, and in plan-view, it im-itates an ancient Roman house (Cenciaioli 2002; Blersch et al.2006). A large door made up of a single travertine slab closedthe entrance. The tomb is divided into ten rooms: one entrancehall (atrium, n. 10) with a rectangular shape and a ceilingimitating a double sloping wooden roof. The tympana, situat-ed on the both sides of the atrium, are decorated with scenesrelated to the afterlife. In addition, four chambers (cubicula, n.1, 2, 8 and 9) and two room accesses (alae, n. 3 and 7), endingin two chambers (n. 4 and 6) are present. At the bottom of theentrance hall, there is a tablinum (n. 5, Fig. 2) with ceilingsembellished with geometric caissons with gorgonian and hu-man protomae.

The lateral cells are empty, with decorations on the walls.In the atrium and in some rooms, several benches, cut into thedeposits, are located along the walls (II, III, VI, VII and inrooms from n. 3 to 7). In the tablinium, seven cinerary urns arepresent: six are Etruscan, made up of travertine and decorated;one, in marble, is Roman. The most noteworthy is named theArunte urn (Arnth Velimnas Aules in Etruscan inscriptions)and consists of a couch adorned with drapery, upon whichthe deceased rests in the typical half-reclining position. Atthe centre of the base, there is the gate of Hades, edged bytwo young-looking winged demons (Fig. 3). The other urnsbelong to the family members (Cenciaioli 2002).

More detailed information is provided by the websites:http://www.archeopg.arti.beniculturali.it/, http://archive.cyark.org/hypogeum-of-the-volumnis-info.

Sedimentological and Lithostratigraphic Assessmentof the Hypogeum

Like several coeval tombs in the area, the VolumniHypogeumholds paint-less walls, thus allowing for a tridimensional viewof the geological features and sedimentary structures. Theenvironment of the hypogean preserved the outcrop fromweathering, which, on the contrary, deeply involves all the

neighbouring outcrops. Due to the importance of the site,sampling is not allowed.

The tomb interior reveals a prevailing hardly cementedgravel body and consistent sand lithology, with only minorclay interposition. The whole sedimentary sequence gentlydips southward; as a consequence, channelled gravel and sandbodies superimpose and partially overlap, from the floor to theroof and from the inner rooms toward the entrance. The ex-posure conditions allow us to reconstruct an about 10 m thickstratigraphic section and to describe the pattern of the sedi-mentary structures. Sedimentological features enable for theidentification of two main depositional units (Fig. 4).

The lowermost channel of unit A is only visible incubiculum n. 4. Here, the large sand bars, concluding thesequence, crop out on the roof (Fig. 5).

The base of unit B crops out above the doorway; the gravel-sand alternation continues in the uppermost subaerial archae-ological site (necropolis of Palazzone). In this part of the sec-tion, massive to roughly organized gravel and large foresetsand bodies prevail. The depositional architecture encom-passes the superposition of six main depositional structures(channels (Ch)), each one roughly composed of a lowermostgravel portion (gravel bedforms (GB)) and an uppermostsandy portion (sand bedforms (SB)). Some details of sedimen-tary structures are visible in Fig. 6.

Thickness, internal structures, gravel/sand ratio and grainsize vary from one channel to the other, and the internal orga-nization of channels evolves throughout the section (Fig. 4). Inthe sedimentological description, we refer to the Hudden-Wentworth grain size scale, as modified by Blair andMcPherson (1999) for coarser classes, and to the lithofaciescodification and the architectural elements hierarchy com-monly used in alluvial deposits (Miall 1985a, b, 1988a, b,1991, 1992; Einsele 1992; Bridge 1993).

Fig. 3 The VolumniHypogeum. From the left to the right: the wall n. IV,the tablinium (room n. 5) with some of the cinerary urns, the wall n. Vandthe two rooms n. 5 and 6. The urn in a frontal position is the Arunte onewith two young-looking winged demons. It is evident a portion of theceiling imitating a double sloping wooden roof

304 Geoheritage (2016) 8:301–314

Unit A

Channel 1 (Ch 1) The lowermost channel is only visible inthe inner tomb (cubiculum n. 4). The base does not crop out inthe tomb perimeter; nevertheless, the emergences of this de-positional body on the walls draw a lenticular geometry, with amaximum thickness of ∼1 m. The coarser channel fill, occu-pying its lowermost portion, is represented by a clast-

supported pebbly conglomerate: grain size varies from 1 to10 cm (fine to very coarse pebbles), with the occurrence ofsome oversized clasts (up to 20 cm). The deposit is moderatelysorted (σ = 1.00Φ sensu Folk andWard 1957), and a coarse tovery coarse sandmatrix is also present. Pebbles are mainly rodto laminar and subordinately equidimensional in shape (ac-cording to the subdivision of Zingg 1935), and subangular tosubrounded (rounding 0.6–0.8: Powers 1953; Pettijohn 1957).

Fig. 4 Stratigraphic section showing the sedimentary sequence exposed along the perimeter walls of the Volumni Hypogeum

Geoheritage (2016) 8:301–314 305

Still represented by lithic, the petrology of clasts is extremelyvariable: grey to light brown limestone and brown to yellow-ish sandstone prevail, with subordinate quartzite and occa-sional green volcanic (probably ophiolites). Clasts usuallyhold a dark brown to reddish oxidation cortex. The conglom-erate is interpreted as a GB, with an internal structure made ofmassive to crude horizontal stratification at the base (faciesGm), passing upward to a planar cross-stratification (faciesGp). A thin lens of plane-parallel laminated fine sand (faciesSh) locally occurs at about 2/3 of the conglomerate. The GB isclosed by an imbricate pebble horizon (Im in Fig. 4). Theuppermost channel fill is represented by planar cross-

laminated medium to fine sand (facies Sp), well sorted, witha lenticular geometry cut to the top by the erosional base ofchannel 2. The Sp laminated body is regarded as a SB.

Channel 2 (Ch2) It can be followed across rooms n. 3 to 7,and walls n. VI and n. VII (Figs. 4, 5 and 6); the erosional baseis only visible in room n. 4. The thickness reaches a maximumof about 2 m, more than half represented by a conglomeratefill. This GB is totally constituted by cross-stratified conglom-erates (facies Gp), with the same textural and petrologicalfeatures previously described. The dark brown to reddish ox-idation cortex is still a widespread feature. The uppermost

Fig. 5 Plan view of spatial disposition of units and channels according to stratigraphic sequence in Fig. 4

306 Geoheritage (2016) 8:301–314

channel fill (SB) starts with a lenticular-shaped sand body,with a small scale through cross-lamination (facies St). Thelens crops out only on walls n. VI and n. VII and throughoutrooms n. 5 and n. 7 (Fig. 5), with a maximum of 50 cm thick-ness. Sand is yellowish in colour, coarse to very coarse-grained and well sorted (σ = 0.5 Ф). The remaining portionof the SB is characterized by well-sorted (σ = 0.5 Ф) parallelcross-laminated sand (facies Sp), with imbricate fine to medi-um pebble at the base. Laminae are normally graded bothupward and downstream, from very coarse sand/granules tocoarse sand.

Channel 3 (Ch3) It crops out extensively along the tombwalls, at about the half of walls height (Figs. 4a, b, c and 5).The bipartition GB-SB of the channel fill is still maintained,with the prevalence of sand. The lowermost GB is here repre-sented by a 50-cm thick conglomerate, with the same texturaland petrological features (including the oxidation surface) ob-served in the previous channels, organized with a throughcross-stratification passing upward to a parallel cross-stratification (transition from Gt to Gp facies). The overlyingSB (Figs. 4b, c and 5) is thicker (up to 1 m) and more articu-lated (composite sand bar). It is organized with threesuperimposed foreset beds identifiable as belonging to faciesSp, showing different foreset inclination: the lower and upper

ones are gently inclined (5° to 10°), whereas the intermediateone is steeper. Laminations of each foreset bed show the samenormal gradation both upward and downstream, from coarsesand to medium and/or very fine sand. Sand is still yellowishin colour and well sorted (σ = 0.5 Ф).

Channel 4 (Ch4) Like the Ch3, it can be followed across therooms (with the exception of room n. 4), and also on the roofand tympanum of rooms n. 10 and n. 5. GB and SB equallydivide the thickness of 1 m (Fig. 5). The lower conglomerateGp, still clast-supported, is cross-stratified and with the samesorting, rounding and petrological composition of clasts; it issignificantly finer, in the class of fine and medium pebbles.Most of pebbles still show a dark brown to reddish oxidationcortex. The SB above is still articulated, with two main foresetbeds, ascribable to facies Sp, steeply and gently inclined, re-spectively (Fig. 6). Yellowish sand is well sorted (σ = 0.5 Ф)and graded, from medium to very fine sand. In room n. 7, thesteeply foreset Sp laminated sand is laterally interrupted by theoccurrence of a lens of massive, light grey silty clay, describedas facies Fl (Fig. 6).

Channel 5 (Ch5) It is present in the cubicula, with the excep-tion of rooms n. 3 and 4, particularly toward the entrance(Fig. 5); the upper portion is mainly visible on the roof. It also

Fig. 6 The stratigraphicsequence as shown along thewalls of the rooms 6 (a) and 7 (b)

Geoheritage (2016) 8:301–314 307

records the thicker deposit (up to 3.5 m). At the base, the GB isthinner (up to 50 cm) and more articulated compared to low-ermost channels (Fig. 5). In rooms n. 6 and 7, it is organized asa clast-supported Gp cross-stratified conglomerate: as forCh4, clasts are fine to medium pebbles, moderately sorted(σ = 1.00 Φ), subangular to subrounded (rounding 0.6–0.8),mainly laminar and equidimensional in shape. The petrologyof clasts does not significantly differ from those describedabove. The dark brown to reddish oxidation cortex also oc-curs. In rooms n. 1, 2, 8 and 9, the channel base is marked byroughly organized matrix-supported clay chips gravel (Fig. 5).Clay plasts still range in the classes of fine and medium peb-bles and are presumably the result of reworking of massivelight grey silty clay, analogously to facies Fl previously de-scribed. The matrix is made of well-sorted (σ = 0.5 Ф) coarsesand. Only locally clay plasts reveal a Gp cross-stratification.On the successive 3 m, three main SB are recognized, eachone about 1 m thick. The lowermost one follows directly theGB and holds two gently inclined foreset beds, recognized asfacies Sp. Yellowish sand is well sorted (σ = 0.5Ф) and grad-ed, from coarse to very fine sand. Each of the two followingSB (grouped as Ch5a) begins with an erosive plane surfaceand clay chips lag, followed by gently inclined Sp cross-laminated very fine sand. These structures only crop out onthe tomb roof and on the tympanum above the entrance.

Unit B

Channel 6 (Ch6) It is not visible in the tomb’s interior be-cause the roof hides it. Along the Hypogeum perimeter, itcrops out above the entry stair, where it reaches 1 m thickness(Figs. 4 and 5). Nevertheless, it belongs to a unit widely doc-umented in the necropolis of Palazzone. A lowermost GBequally divides the visible part of Ch6 and a SB discussedabove. GB comprises a clast-supported massive to roughlyorganized gravel: at the base, massive to crude stratified finecobbles gravel prevail (facies Gm), whereas horizontally bed-ded coarse to fine pebbles gravels (facies Gh) are visible in theupper part. The deposit is moderately sorted (σ = 1.00 Φ);rounding is extremely variable: clasts vary from angular torounded and are mainly discoid to equidimensional in shape.Regarding petrology, white to light grey limestone prevail,with minor sandstone. The oxidation surface is only rarelydocumented. A subordinate yellowish to light brown verycoarse sand/granules matrix also occurs. The SB is organizedas a high-angle cross-laminated sand (still regarded as faciesSp): the yellowish to light brown sand grades from coarsesand to medium sand.

Paleodepositional Inferences

The sedimentary features justify the distinction of two depo-sitional units. Nevertheless, deposits are all referable to

channelled stream processes and identify a roughly organizedhigh-energy river environment. The alternation of gravel andsand transport and deposition testifies for a variable streamregime, in which high- and low-energy conditions alternated,thus reflecting on the amount and type of solid load.Paleocurrent measurements reveal a dispersion of flow direc-tions between SW and SSE for unit A and a main W-WSWdirection for unit B. Thus, flows document repeated divaga-tions from the main channel axes. The whole structures indi-cate a downstreammigration; nevertheless, the grow directionfor gravelly and sandy structures is different. Therefore, abraided river depositional exposure, although periodical, canbe reconstructed. The oxidation surface, common on gravelsof unit A, denotes a subaerial although periodical exposure.Deposits of unit A result from the fill of shallow braidedchannels: although we consider a single section, the river sys-tem clearly evolves upward, from a gravel-dominated envi-ronment (e.g.: Scott type: Miall 1992) to a large sandbar-dominated environments (Platte type: Miall 1992). Both thepetrology of gravel and the textural features are steady, and aunique basin supply and drainage system appears as a reason-able hypothesis. The variation in grain size for the bed loadprobably indicates a long time evolution with the same baselevel, allowing for a progressive river organization, particular-ly on a foothill area. Conversely, gravels of unit B almosttotally lack of surface oxidation (particularly the uppermostdeposits cropping out in the Palazzone area). They are roughlyorganized and less rounded, whereas sands show high-angleforesets. Such features characterize a deep channel braidedriver (e.g.: Donjek type: Miall 1992) and sedimentation in atectonic active basin. A possible interpretation for the transi-tion from unit A to unit B is a landscape rejuvenation and anew energy of relief, connected to a change in the boundaryconditions as a new local base level for tectonic movement orclimate change.

The Hypogeum in the Geologicaland Geomorphological Setting of the Perugia Hill

The Volumni Hypogeum was carved inside the same depositsthat characterize the hill of Perugia, where the town is settled.To highlight the key role of this Etruscan grave as archaeo–geosite and in order to illustrate how the stratigraphic se-quence, exposed along the hypogeum walls, could be usedas of 3D guide is necessary to resume the geological andgeomorphological evolution of the study area.

Perugia developed on a triangular-shaped hill, elongated ina NW-SE direction, with a medium altitude value of493 m a.s.l. overlaying an area of about 27 km2 (Fig. 7).

The limits of the hill are referred to fluvial-lacustrine units(Pleistocene, Fig. 7). The deposits are enclosed in the bedrock(Oligocene-Miocene) cropping out along the SW, N and NE

308 Geoheritage (2016) 8:301–314

boundaries, whereas, toward SE, alluvial sediments(Holocene) of the Tiber River delimit the study area. Thehighest part of the rise is coincident with the north-westernapex, where the historical centre of the town is built. From thispoint, four main branches spread out toward SEwith a generaldecrease in altitude (Fig. 7). The slope angle varies between 1°and 45°; 41 % of the area is between 0° and 9°, 37 % between9° and 15° and only the remaining 22 % is above 15° (Fig. 7).The morphological setting is similar to rounded hills, with thesteeper areas restricted only in the northern part or along theeastern slopes. Narrow and steeper streams, tributaries of theTiber River, divide each branch.

The geological origin of the area is related to the recentevolution of northern Apennine. Through Oligocene andMiocene, the entire central Italy experiences a compressionaltectonic phase, related to the eastward migration of theApennine chain-foredeep basin-foreland system. The latter ischaracterized by anticlines alternated to narrow synclines,with NW-SE direction. An extensional regime followed thecompressional phase (Miocene-Pliocene) producing differentsets of normal faulting (Malinverno and Ryan 1986; Collettiniet al. 2000). Several other sets of normal faults (mainly ori-ented in Apennine and anti-Apennine directions) have beenactive since Late-Early Pleistocene (Calamita and Deiana1986); moreover, isostatic uplift started in the Middle-LatePleistocene and is still active (Ambrosetti et al. 1982;D’Agostino et al. 2001). From Pliocene onward, this complex

tectonic framework led to the setting of several intermountainbasins, bounded by normal fault systems and filled with flu-vial and/or lacustrine deposits (Martini and Sagri 1993;Napoleone et al. 2003).

The Tiberino Basin was the largest among the intermoun-tain Umbrian basins (about 1800 km2) and crosses the entireregion form north to south, dividing into two branches nearPerugia, with a Boverturned Y^ shape (Ambrosetti et al. 1995;Basilici 1997; Fig. 8).

The basin was not a unique depression, but it was constitutedby several minor coalescing subbasins, each one characterized bydifferent sedimentary environments and by a peculiar evolutionin time and space. Both deep and shallow lakes, alluvial plainand/or palustrine environments, where the low energy fine-grained deposits prevailed, are overlaid and/or interbedded withcoarser sediments (gravel and sand), related to more energetictransport and deposition mechanisms. The cause relies on theriver drainage network activity, flowing from the surroundinghills and shaping alluvial fans or debris flows along the basinboundaries, and also representing the river channel depositsalong the valleys. From Early Pleistocene onward, flood-plainenvironments largely dominate the basin, drained by main riverswith lacustrine to swampy conditions (Ambrosetti et al. 1995;Cattuto et al. 1995; Basilici 2000; Bizzarri et al. 2011; Cherinet al. 2012, 2014; Melelli et al. 2014; Pucci et al. 2014). Thissedimentary setting at the transition across subaerial conditionscreates complex resulting sedimentary structures.

Fig. 7 The hill of Perugia. (1)The dot is the VolumniHypogeumlocation. Slope values, (2) 0°–9°,(3) 9°–15°, (4) >15°. The areabounded by continuous line is thehistorical centre of the town.(UPSA, UPSG, UPDD, SSV,ASM) significant outcrops of thestratigraphic units cited in the text

Geoheritage (2016) 8:301–314 309

Perugia is built along the western boundary of Tiber valley.The present day topographic assessment, with narrow valleysand numerous fluvial, gravitational and anthropic scarps, al-lows us to observe meaningful outcropping areas and to rec-ognize different sedimentary environments. The different dis-tribution of slope angles suggests an organized arrangement ofthe sediments that show a different grain-size compositionalong the entire relief (Fig. 7). The Perugia hill deposits havebeen interpreted as a fan delta (sensu Leeder et al. 1988, andNemec and Steel 1988) of the ancient Tiber River that, inPliocene and Pleistocene times, followed a different path andflew into the lacustrine environment of the Tiberino Basin

near Perugia (Cattuto and Gregori 1988; Fig. 8). Accordingto this interpretation, the hill was referred to as a single sedi-mentary unit where, from the hilltop downwards, the topset(upper hill), the foreset (intermediate part of the hill) and thebottomset (at the foothill) subenvironments are recognized.Recent investigations and new data (Fig. 7, Manassei 2014)based on the different lithological and sedimentological fea-tures of deposits lead to alternative interpretations.

Five main types of deposits are recognized (Fig. 7), allreferred to Early-Middle Pleistocene, according to literaturedata (De Angeli d’Ossat 1918; Petronio et al. 2000–2002;Argenti 2004):

Fig. 8 The ancient Tiber Riverpath according to Cattuto andGregori (1988) palaeogeographicreconstruction. The dashed linetracks the paleo pattern ending asa fan delta near Perugia andbuilding up the actual hill wherethe town is built (modified fromCattuto and Gregori, 1988). Onthe top: the Tiberino basin area inUmbria region and Perugialocation

310 Geoheritage (2016) 8:301–314

Type 1. (ASM): clayey silt deposits rarely cropping out.Clays are mainly identifiable from the morpholog-ical response and the lowest slope values.

Type 2. (SSV): prevailing fine to coarse sand bodies, with acommon lenticular shape and a thickness of sometens of metres. In spite of the lack of sedimentarystructures, they are referred to as traction currents;the rare occurrence of plane-parallel lamination infiner sands is hypothetically related to a low energyenvironment.

Type 3. (U PSG): alternated clasts-supported conglomeratesand coarse sand beds. Coarser clasts are mainlymoderately rounded sandstone pebbles to cobbles.The thickness of sandy layers is variable, from fewcentimetres up to ∼1 m.

Type 4. (U PSA): matrix-supported conglomerates. Clastsare well-rounded sandstones, with subordinatelimestone or red/black chert, varying from fewcentimetres to a maximum of 15–20 cm (mediumpebbles to coarse cobbles).

Type 5. (U PDD): massive, poorly organized to roughlystratified conglomerates, with bed thickness vary-ing from 1 to 2 m up to several metres. Pebbles andcobbles, with diameters from few centimetres to10–20 cm, are interposed to boulders, with a max-imum size of up to 50 cm.

In this reconstruction, deposits of type 1 and 2 are referredto a low energy alluvial and/or lacustrine environment, par-tially heteropic (uppermost part), to a well-developed fluvialenvironment (type 3 and 4 deposits). Type 5 deposits representthe last depositional event and are attributed to high-energyalluvial environment, in the proximity of the feeding areas.

Discussing the validity of previous interpretations is beyondthe aims of this work. On the basis of both the sedimentologicalanalysis and of topographic considerations, the VolumniHypogeum is excavated into the topset/foreset deltaic depositsof Cattuto and Gregori (1988), or into type 3 deposits ofManassei (2014). The new sedimentological data, indeed, linkdeposits of the Hypogeum to a fluvial environment and particu-larly to river channels. Nonetheless, none of the previous recon-struction looks completely satisfactory, and new geological andsedimentological investigations on the Perugia hill are needed.

Geosite, Archaeological Site or Archaeo–Geosite?

The investigation of the geological heritage in Italy has fo-cused on the identification and enhancement of geosites andgeological routes (Poli 1999; Panizza 2001; Carton et al.2005; Coratza and Giusti 2005; Gregori et al. 2005; Gregoriand Melelli 2005; Reynard and Panizza 2005; Reynard andCoratza 2007). Geosites have been identified in the whole

national territory (Brancucci and Burlando 2001; Panizza2001; Castaldini et al. 2005; Piacente 2005).

Because of the great variability of its lithological substrateand of the complexity of its geomorphological evolution, theUmbria region holds a large number of geological and geo-morphological sites with relevant scientific and cultural values(Gregori et al. 2005). Moreover, the Umbria region has one ofthe most relevant archaeological and historical heritages inItaly. The value of a geosite has to be evaluated according tosome parameters (Gray 2004):

– An intrinsic value: Brefers to the ethical belief that somethings are of values simply for what they are rather thanwhat they can be used for by humans (utilitarian value)^(Gray 2004).

– Cultural and aesthetic values: assigned by a communityfor which a particular site plays an important role in termsof cultural and historical heritage.

– Economic value: in economically depressed areas, thegeosites can be an important starting point for the localeconomy, becoming a centre of attraction for the localtourist flow.

– Scientific and educational value: the importance ofgeosites as a topic of scientific research, teaching anddissemination.

As a consequence, in Umbria, two main classes of geositesare recognizable. In the first group, the scientific value ofgeosites is strongly improved by cultural and historical values;in the second one, the naturalistic, geological and geomorpho-logical importance prevails (Gregori et al. 2005). Amonggeosites with a relevant cultural value, some notable townsof Etruscan and medieval origin are present, such as Perugia,Orvieto, Gubbio and Assisi. The following towns representexcellent examples of attractive sites due to the presence ofparticular geological and geomorphological features: Perugiaand the geological structure of the hill; Orvieto and the volca-nic mesa superimposed on Pliocene-Pleistocene clays;Gubbio and the intermountain basin with the master faultsbordering the city (triangular facets); Assisi and the Subasiomountain with spectacular macro dolines on the top. All thesesites are characterized by both an excellent geological contextand a unique cultural heritage with historical, architectural andarchaeological values.

An archaeological site where the geological substratumand/or the geomorphological evolutionary conditions are de-terminant for the knowledge and correct interpretation of thesite itself can be defined as archeo–geosite. Moreover, part ofthis relevant heritage is subjected to hazard conditions due tothe changes of the natural environmental conditions. Recently,several studies (Fronzek et al. 2006; Prosser et al. 2010) dem-onstrated that a real risk related to the geodiversity conserva-tion is particularly present in those geographic areas where

Geoheritage (2016) 8:301–314 311

global climate changes are acting with increasing tempera-tures and rainfall values. The result is the triggering of newmorphogenetic processes or a faster action of the existingones. Because of this, with the art. 2 of the Convention onthe Protection of World Cultural and Natural Heritage(UNESCO) signed in Paris in 1972, the international scientificcommunity has started the identification of areas having highvalue of geodiversity. Several international projects havefollowed the same line of research, mostly sponsored byUNESCO (United Nations Educational, Scientific andCultural Organization), including the one presented in 1996in collaboration with the IUGS (International Union ofGeological Sciences), named BGeosites^. The aim of the pro-ject was the definition and identification of geosites (Clealet al. 1999). The addition of the archaeological importanceto a geosite is a unique opportunity to increase the value andthe attractiveness of the site.

The Hypogeum is probably one of the most famousEtruscan graves in central Italy, which attracts an importantflow of tourists interested in the Etruscan civilization. As wehave shown here, the Hypogeum is also a unique opportunityto link the Archaeology to the Earth Sciences. The site is a firstattempt to increase the knowledge about the geological historyof the area and for promoting new research opportunities, thelocalization and the management of archaeo–geosites. Thebroader goal of this research is to include the Hypogeum ina wide geotouristic network, named AGE (ArcheoGEosite)and connecting the main Etruscan graves located in centralItaly.

Conclusions

From a geological point of view, when an archaeological site iscarved in the underground, it represents a rare opportunity toinvestigate the outcropping rocks and their distinctive character-istics. The excavation, if articulated in ceilings, floors and perim-eter walls, provides a unique 3D view of the outcrop. The type ofterrain (grain size, sedimentary structures, vertical and horizontalorganization) is a basic marker of the palaeogeographic deposi-tional environment. Thus, an archaeological site is an excellentpiece of the puzzle that a geologist must complete trying toreconstruct the evolutionary history of an area.

In this paper, we have shown that the Volumni Hypogeumplays a key role in the palaeogeographic reconstruction of thePerugia hill (Umbria, central Italy). The idea is also to stressthe importance of connecting the archaeological value of a siteto its geological significance in order to allow for a deeperknowledge of its characteristics. The same approach can bepotentially applied to other underground sites to build a net-work of archeo-geosites with similar characteristics. Theknowledge of the features of the fluvial-lacustrine depositsconstituting the Perugia hill has been strongly improved by

the analysis of the Etruscan sites located in the area. Thedifferences in grain size and lithology, and the spatial distri-bution both in the vertical and in the horizontal direction,reflect in the topographic and morphologic setting of the hill.Moreover, despite the intensive human settlement and theconsequent changes of the surface morphology, the Perugiahill still maintains the evidence of the geological history andof the geomorphological transformations.

In addition, it must be stressed that Archaeology andGeology can be useful to each other. If archaeologicalelements contribute to a better reconstruction of the geo-logical evolution of a larger area (i.e. through the analysisof a stratigraphic sequence, as we did in this work), thegeological interpretation provides, in turn, at least twobenefits to the archaeological research. First, it providesnew clues to interpret the choice of the location wherethe graves were located. Indeed, although it is well recog-nized that the disposition of the necropolis depends onsome cultural, historical and religious parameters, it is alsoobvious that the lithological nature of the substrate (typeand arrangement of the deposits or rocks) is a fundamentalcondition that must be taken into account to select thesite. The Volumni Hypogeum is a good example of that.The walls and the floor were excavated where the coarserfraction of deposits was present, with conglomerates pre-vailing upon the sands. The ceiling, where the decorationsare abundant, is graven along thick sand deposits. Theother benefit deriving from the geological investigationof archaeological sites is that, when the geological andgeomorphological knowledge of the entire area is wellknown, other potential sites placed in similar geologicalconditions (i.e. similar stratigraphic characteristics) couldbe discovered. Indeed, under the assumption that the geo-logical and topographic setting observed in a studied siteis representative of favourable excavation conditions, thegeological map and the stratigraphic correlations might bea useful and potentially unique tool for further investiga-tions and research campaigns.

Therefore, the use of well-known archaeological sites toinvestigate and highlight the geological component of a terri-tory represents a conceptual model to promote a new synergybetween Archaeology and Geology and also increases theeconomic value of the sites, related to tourism. Differentmethods addressing the treatment and the interpretation ofspatial data are available (Gregori and Melelli 2005; Charouet al. 2010; Gavrila et al. 2011; Melelli et al. 2012). Resultsderiving from studies like the one presented in this paper canbe used to build geotouristic itineraries in WebGIS platforms.These itineraries could connect the main archaeo–geosites al-so improving, where possible, the natural and anthropogenicvalues already present in the areas. Moreover, the use ofWebGIS platforms could also allow for a free visualizationand a user-friendly fruition of information on digital devices.

312 Geoheritage (2016) 8:301–314

Acknowledgments This paper is dedicated to the memory of our col-league, Prof. Lucilia Gregori, who recently passed away. Lucilia was anenthusiast promoter and developer of the idea of strengthening the syn-ergy between archaeology, geology and tourism. This paper is a concretedemonstration of the innovative thinking of Lucilia during her eclecticand, unfortunately, too short research career.

References

Ambrosetti P, Basilici G, Capasso-Barbato L, CarboniMG, Di Stefano G,Esu D, Gliozzi E, Petronio C, Sardella R, Squazzini E (1995) IlPleistocene inferiore nel ramo Sud occidentale del bacino tiberino(Umbria): aspetti litostratigrafici e biostratigrafici. Il Quaternario 8:19–36

Ambrosetti P, Carraro F, Deiana G, Dramis F (1982) Il sollevamentodell’Italia Centrale tra il Pleistocene inferiore ed il Pleistocenemedio. Contributi conclusivi per la realizzazione della CartaNeotettonica d’Italia (parte II). Progetto Finalizzato GeodinamicaSottoprogetto Neotettonica – CNR, 513:219–223

Argenti P (2004) Plio-quaternary mammal fossiliferous sites of Umbria(central Italy). Geol Romana 37:67–78

Asrat A, Zwoliński Z (2012) Geoheritage: from geoarchaeology togeotourism. Quaestiones Geographicae 31:5–6

Barker G, Rasmussen T (1998) The Etruscans. Blackwell, OxfordBasilici G (1997) Sedimentary facies in an extensional and deep-

lacustrine depositional system: the Pliocene Tiberino Basin,Central Italy. Sediment Geol 109:73–94

Basilici G (2000) Floodplain lake deposits on an early Pleistocene alluvialplain (Tiberino Basin, Central Italy). In E.H. Gierlowski - KordeschandK.R. Kelts (Eds.), Lake basins through space and time (pp. 535–542). AAPG Studies in Geology, 46.

Bizzarri R, Albianelli A, Argenti P, Baldanza A, Colacicchi R, NapoleoneG (2011) The latest continental filling of Valle Umbra (Tiber basin,central Italy) dated to one million years ago by magnetostratigraphy.Il Quaternario 24:51–65

Blair TC, McPherson JG (1999) Grain size and textural classification ofcoarse sedimentary particles. J Sediment Res 69:6–19

Blersch D, Balzani M, Tampone G (2006) The Volumnis’ Hypogeum inPerugia, Italy. Application of 3D survey and modelling in archaeo-logical sites for the analysis of deviances and deformations, FromSpace to Place: Proceedings of the 2nd International Conference onRemote Sensing in Archaeology. Archeopress, Oxford, pp. 389–394

Brancucci G, Burlando M (2001) La salvaguardia del patrimoniogeologico. Scelta strategica per il territorio. L'esperienza dellaLiguria. Milano, Franco Angeli Editore

Bridge JS (1993) Description and interpretation of fluvial deposits: acritical perspective. Sedimentology 40:801–810

Calamita F, Deiana G (1986) Geodinamica dell’appennino umbro-marchigiano.Memorie Della Società Geologica Italiana 35:311–316

Carton A, Coratza P, Marchetti M (2005) Guidelines for geomorpholog-ical sites mapping: examples from Italy. Géomorphologie: Relief,Processus, Environnement 2:209–218

Castaldini D, Valdati J, Ilies DC, Chiriac C, Bertogna I (2005) Geo-touristmap of the natural reserve of Salse di Nirano (Modena Apennines,northern Italy). Il Quaternario 18:245–255

Cattuto C, Cencetti C, Fisauli M, Gregori L (1995) I bacini pleistocenicidi Anghiari e Sansepolcro nell’alta Valle del F. Tevere. IlQuaternario 8:119–128

Cattuto C, Gregori L (1988) Il colle di Perugia: geologia, idrogeologia,geomorfologia. Bollettino Della Società Geologica Italiana 107:131–140

Cenciaioli L (2002) Ipogeo dei Volumni e Necropoli del Palazzone.Attività culturali. Perugia: Soprintendenza per i Beni Archeologicidell’Umbria, Tipografia T.S.M. s.n.c. Ponte Valleceppi.

Charou E, Kabassi K, Martinis A, Stefouli M (2010) IntegratingMultimedia GIS Technologies in a Recommendation System forGeotourism. In G.A. Tsihrintzis and Jain L.C. (Eds.), MultimediaServices in Intelligent Environments (pp. 63–75). Smart Innovation,Systems and Technologies, 3: Springer.

Cherin M, Baldanza A, Barchi MR, Bizzarri R, Buratti N, Caponi T,Grossi F, Pandolfi L, Pazzaglia F (2014) Nuovi recuperi nel sitodel Pleistocene inferiore di Ellera di Corciano (Perugia). Giornatedi Paleontologia XIVedizione - Bari, 11–13 Giugno 2014 - Volumedei Riassunti, 90–91.

Cherin M, Bizzarri R, Buratti N, Caponi T, Grossi F, Kotsakis T, PandolfiL, Pazzaglia F, Barchi MR (2012) Multidisciplinary study of a newquaternary mammal-bearing site from Ellera di Corciano (centralUmbria, Italy): preliminary data. Rend Online Soc Geol Ital 21:1075–1077

Cleal CJ, Thomas BA, Bevins RE, Wimbledon WAP (1999)GEOSITES—an international geoconservation initiative. GeolToday 15(2):64–68

Collettini C, Barchi MR, Pauselli C, Federico C, Pialli G (2000) Seismicexpression of active extensional faults in northern Umbria (CentralItaly). J Geodyn 29:309–321

Coratza P, Giusti C (2005)Methodological proposal for the assessment ofthe scientific quality of geomorphosites. Il Quaternario 18:307–313

D’Agostino N, Jackson J, Dramis F, Funiciello R (2001) Interactionsbetween mantle upwelling, drainage evolution and active normalfaulting: an example from the central Apennines (Italy). Geophys JInt 147:475–497

De Angelis D’Ossat G (1918) Rinvenimento di mammiferi fossili nelPliocene lacustre e salmastro umbro. Bollettino Della SocietàGeologica Italiana 37:39–45

Dowling RK, Newsome D (2006) Geotourism. Routledge, LondonEinsele G (1992) Sedimentary Basins. Evolution, Facies, and Sediment

Budget. Springer-Verlag, BerlinFolk RL, Ward W (1957) Brazos River bar: a study in the significance of

grain size parameters. J Sediment Petrol 27:3–26Fronzek S, Luoto M, Carter TR (2006) Potential effect of climate change

on the distribution of palsa mires in subarctic Fennoscandia. ClimRes 32:1–12

Gavrila IG, Man T, Surdenau V (2011) Geomorphological heritage as-sessment using GIS analysis for geotourism development in MacinMountains, Dobrogea, Romania. GeoJournal of Tourism andGeosites 2:198–205

Ghilardi M, Desruelles S (2009) Geoarchaeology: where human, socialand earth sciences meet with technology. Survey and PerspectivesIntegrating Environment and Society [Online], 2.2, Url http://sapiens.revues.org/422.

Goldberg P,Macphail RI (2005) Practical and theoretical geoarchaeology.Blackwell Publishing Ltd., Malden

Gordon JE (2012) Rediscovering a sense of wonder: geoheritage,geotourism and cultural landscape experiences. Geoheritage 4:65–77

Gray M (2004) Geodiversity valuing and conserving abiotic nature. JohnWiley and Sons Ltd., Chichester

Gregori L, Melelli L (2005) Geoturism and geomorphosites: the GISsolution. Il Quaternario 18(1):285–292

Gregori L, Melelli L, Rapicetta S, Taramelli A (2005) The maingeomorphosites in Umbria. Il Quaternario 18:93–101

Güngör Y, Iskenderoglu L, Azaz D, Güngör B (2012) Geopark inventorystudy of Levent valley, Akçadag-Malatya. InternationalMultidisciplinary Scientific GeoConference: SGEM: SurveyingGeology & Mining Ecology Management 1:125

Gustavsson M, Kolstrup E, Seijmonsbergen AC (2006) A new symbol-and-GIS based detailed geomorphological mapping system: renewal

Geoheritage (2016) 8:301–314 313

of a scientific discipline for understanding landscape development.Geomorphology 77:90–111

Haynes S (2000) Etruscan civilization. British Museum Press, LondonLeeder MR, Ord DM, Collier R (1988) Development of alluvial fans and

fan deltas in neotectonic extensional settings: implications for theinterpretation of basin fills. In: Nemec W, Steel RJ (eds) Fan deltas:sedimentology and tectonic settings. Blackie and Son, Glasgow, pp.173–185

Malinverno A, Ryan WB (1986) Extension in the Tyrrhenian sea andshortening in the Apennines as a result of arc migration driven bysinking of the lithosphere. Tectonics 5:227–246

Manassei D (2014) Siti archeologici nella geologia del Colle di Perugia.In: L. Melelli, C. Pauselli, C. Cencetti (Eds.) Atti del ConvegnoNazionale BDialogo intorno al Paesaggio^. Perugia, 19–22 febbraio2013. Culture territori linguaggi, 4, 2014, II: 246–257 ISBN9788890642159.

Martini IP, Sagri M (1993) Tectono-sedimentary characteristics of lateMiocene quaternary extensional basins of the north Appennines,Italy. Earth Sci Rev 34:197–223

Melelli L (2014) Geodiversity: a new quantitative index for naturalprotected areas enhancement. GeoJournal of Tourism and GeositesISSN 2065-0817, E-ISSN 2065-1198. VII, no. 1, vol. 13,May 2014,p. 2–12 Article no. 13103–142.

Melelli L, Gregori L, Mancinelli L (2012) The use of remote sensed dataand GIS to produce a digital geomorphological map of a test area inCentral Italy. Remote Sensing of Planet Earth, Y. Chemin, (Ed.),ISBN 979-953-307-541-8, InTech, Available from: http://www.intechopen.com/articles/show/title/ the-use-remote-sensed-data-and-gis-to-produce-a-digital-geomorphological-map-of-a-test-area-in-centr.

Melelli L, Pucci S, Saccucci L, Mirabella F, Pazzaglia F, Barchi M (2014)Morphotectonics of the upper Tiber valley (northern Apennines,Italy) through quantitative analysis of drainage and landforms.Rendiconti Lincei 25(2):129–138

Miall AD (1985a) Architectural-element analysis: a newmethod of faciesanalysis applied to fluvial deposits. Earth Sci Rev 22:261–308

Miall AD (1985b) Architectural-element analysis: a newmethod of faciesanalysis applied to fluvial deposits. In R.M. Flores, F.G. Etheridge,A.D. Miall, W.E. Galloway and T.D. Louch (Eds.), Recognition ofFluvial Depositional Systems and Their Resource Potential (pp. 33–81). SEPM Short Course Notes, 19.

Miall AD (1988a) Facies architecture in clastic sedimentary basins. In:Kleinspehn KL, Paola C (eds) New perspectives in basin analysis.Springer-Verlag, Berlin, pp. 67–81

Miall AD (1988b) Architectural elements and bounding surfaces in flu-vial deposits: anatomy of the Kayenta formation (lower Jurassic),southwest Colorado. Sediment Geol 55:233–262

Miall AD (1991) Hierarchies of architectural units in clastic rocks, andtheir relationship to sedimentation rate. In A.D. Miall and N. Tyler(Eds.), The Three-Dimensional Architecture of Terrigenous ClasticSediments, and its Implications for Hydrocarbon Discovery andRecovery (pp. 6–12). SEPM Concepts in Sedimentology andPaleontology, 3.

Miall AD (1992) Alluvial deposits. In R.G.Walker and N.P. James (Eds.),Facies Models: Response to Sea-Level Change (pp. 119–142). St.John’s: Geological Association of Canada.

Moore ID, Grayson RB, Ladson AR (1991) Digital terrain modeling: areview of hydrological, geomorphological, and biological applica-tions. Hydrol Process 5:3–30

Napoleone G, Albianelli A, Azzaroli A, Bertini A, Magi M, Mazzini M(2003) Calibration of the upper Valdarno basin to the Plio-Pleistocene for correlating the Apennine continental sequences. IlQuaternario 16:131–166

Nati D, Nardelli S (2010) Le necropoli di Perugia. Città di Castello,Edimond

Nelson A, Reuter HI, Gessler P (2009) DEM production methods andsources. In: Hengl T, Reuter H (eds) Geomorphometry: Concepts,Software, Applications (pp. 65–85). Developments in Soil Science,33. Elsevier, Amsterdam

Nemec W, Steel RJ (1988) What is a fan-delta and how do we recognizeit? In: Nemec W, Steel RJ (eds) Fan deltas: sedimentology andtectonic settings. Blackie and Son, Glasgow, pp. 3–13

Panizza M (2001) Geomorphosites: concepts, methods and examples ofgeomorphological survey. Chin Sci Bull 46:4–5

Panizza M, Piacente S (2008) Geodiversità: messa a punto concettuale emetodologie di valutazione. Quaderni dell’Accademia delle Scienzedi Torino.

Petronio C, Argenti P, Caloi L, Esu D, Girotti O, Sardella R (2000–2002)Updating villafranchian mollusc and mammal faunas of Umbria andLatium (Central Italy). Geol Romana 36:369–387

Pettijohn FJ (1957) Sedimentary rocks. Harper and Row, New YorkPiacente S (2005) Geosites and geodiversity for a cultural approach to

geology. Il Quaternario 18:11–14Pica A, Vergari F, Fredi P, Del Monte M (2015) The Aeterna Urbs geo-

morphological heritage (Rome, Italy). Geoheritage 1-12. doi:10.1007/s12371-015-0150-3

Poli G (1999) Geositi. Testimoni del tempo. Regione Emilia Romagna,Servizio Paesaggi, Parchi e Patrimonio Naturale. Bologna: GraficheDamiani.

Powers MC (1953) A new roundness scale for sedimentary particles. JSediment Petrol 23:117–119

Prosser CD, Burek CV, EvansDH, Gordon JE, Kirkbride VB, Rennie AF,Walmsley CA (2010) Conserving geodiversity sites in a changingclimate: management challenges and responses. Geoheritage 2:123–136

Pucci S, Mirabella F, Pazzaglia F, Barchi MR, Melelli L, Tuccimei P,Saccucci L (2014) Interaction between regional and local tectonicforcing along a complex quaternary extensional basin: upper Tibervalley, northern Apennines, Italy. Quat Sci Rev 102:111–132

Rapp Jr GR, Hill CL (1998) Geoarchaeology: the earth science approachto archaeological interpretation. Yale University Press, New Haven

Reynard E, Coratza P (2007) Geomorphosites and geodiversity: a newdomain of research. Geographica Helvetica 62:138–139

Reynard E, Panizza M (2005) Geomorphosites: definition, assessmentand mapping. Géomorphologie: Relief, Processus, Environnement3:177–180

Vernesi C, Caramelli D, Dupanloup I, Bertorelle G, Lari M, Cappellini E,Moggi-Cecchi J, Chiarelli C, Castrì L, Casoli A, Mallegni F,Lalueza-Fox C, Barbujani G (2004) The Etruscans: a populationgenetic study. Am J Hum Genet 74:694–704

Waters MR (1992) Principles of geoarcheology: a north American per-spective. University of Arizona Press, Tucson

Zingg T (1935) Beitrag zur schotteranalysis. Schweiz Mineral PetrogrMitt 15:39–140

314 Geoheritage (2016) 8:301–314