B08_ copertina_R_OK C August 20-28,2004 Florence -

Field Trip Guide Book - B08 ON HUMANSETTLEMENTS EVOLUTION, ANDIMPACT FACTORS, TEMPORAL FRAMEWORK, TRIGGERING GEOMORPHOLOGICAL SOUTHERN-CENTRAL ITALY: PHENOMENA IN GRAVITATIONAL LARGE SCALE Pre-Congress 32 GEOLOGICAL CONGRESS Volume n°1-fromPR01toB15 M. DelPrete,B.Gentili,F.M. Guadagno,P. Tacconi Associate leaders: F. Dramis,A.Prestininzi Leaders: nd INTERNATIONAL B08 28-05-2004, 19:13:29 The scientific content of this guide is under the total responsibility of the Authors

Published by: APAT – Italian Agency for the Environmental Protection and Technical Services - Via Vitaliano Brancati, 48 - 00144 Roma - Italy

Series Editors: Luca Guerrieri, Irene Rischia and Leonello Serva (APAT, Roma)

English Desk-copy Editors: Paul Mazza (Università di Firenze), Jessica Ann Thonn (Università di Firenze), Nathalie Marléne Adams (Università di Firenze), Miriam Friedman (Università di Firenze), Kate Eadie (Freelance indipendent professional)

Field Trip Committee: Leonello Serva (APAT, Roma), Alessandro Michetti (Università dell’Insubria, Como), Giulio Pavia (Università di Torino), Raffaele Pignone (Servizio Geologico Regione Emilia-Romagna, Bologna) and Riccardo Polino (CNR, Torino)

Acknowledgments: The 32nd IGC Organizing Committee is grateful to Roberto Pompili and Elisa Brustia (APAT, Roma) for their collaboration in editing.

Graphic project: Full snc - Firenze

Layout and press: Lito Terrazzi srl - Firenze

B08_ copertina_R_OK D 24-05-2004, 15:15:06 Volume n° 1 - from PR01 to B15

32nd INTERNATIONAL GEOLOGICAL CONGRESS LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS, TEMPORAL EVOLUTION, AND IMPACT ON HUMAN SETTLEMENTS

LEADERS: F. Dramis1, A. Prestininzi2 ASSOCIATE LEADERS: M. Del Prete3, B. Gentili4, F.M. Guadagno5, P. Tacconi6 AUTHORS: M.-G.Angeli7, F. Bozzano2, C. Cencetti6, P. Conversini6, M. Del Prete3, B. Gentili4, F.M. Guadagno5, G. Pambianchi4, F. Pontoni7, G. Scarascia Mugnozza2, P. Tacconi6 EDITORS: F. Dramis1, G. Fubelli1

1 Università “Roma Tre”, Roma - Italy 2 Università “La Sapienza”, Roma - Italy 3 Università della , Potenza - Italy 4 Università di Camerino - Italy 5 Università di Sannio, Benevento - Italy 6 Università di Perugia - Italy 7 National Research Council, Perugia - Italy 8 Geoequipe Consulting, Tolentino - Italy

Florence - Italy August 20-28, 2004 Pre-Congress B08

B08_R_OK A 24-05-2004, 15:18:28 Front Cover: A debris fl ow tongue from the May 1988 Sarno catastrophic event (photo by F.M. Guadagno).

B08_R_OK B 24-05-2004, 15:18:30 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

TEMPORAL EVOLUTION, AND IMPACT ON HUMAN SETTLEMENTS B08

Leaders: F. Dramis, A. Prestininzi Associate Leaders: M. Del Prete, B. Gentili, F.M. Guadagno, P. Tacconi

Landslides in Italy As far as climatic conditions are concerned, the Italian F. Dramis, A. Prestininzi peninsula is often affected by the infl uence of humid- warm air masses coming from the west and south, to Introduction which heavy rainfall events (up to more than 2000 Landslides are widespread in Italy due to the nature mm/year) are related. Long lasting precipitation (up of the bedrock, which is largely made of soft rocks or to more than 500 mm in 72 hours), to which a large densely-fractured hard rocks, the rugged topography number of landslides and heavy fl oods are related, and the frequent recurrence of high magnitude represent recurrent phenomena in the fall season (e.g. triggering factors, such as seismic shocks, and Polesine, 1951 and 1957, Reggio Calabria, 1953, extreme rainfall events (Agnesi et al. 1982; Mazzalai, Florence and Venice, 1966, Piemonte-Val d’Aosta, 1980; Canuti et al., 1988; Catenacci, 1992; Dramis et 1993, 2000). Also short-lived intense rainfall can al., 1998). locally trigger catastrophic landslides (e.g. Salerno- In relation with the above-mentioned features, different Amalfi , 1954; Mt. Etna, 1995, Versilia and Friuli, types of landslides are produced, even if their spatial 1996; Sarno, 2000). distribution and density are not homogeneous all over The high population density of mountain valleys, the Italian territory (Cotecchia, 1978; Canuti, 1983; piedmont belts, and the location of numerous Urciuoli, 1988; Dramis et al., 2002). Figures 1.1 and urban settlements on top of hills modeled in soft 1.2 show distribution models of land susceptibility bedrock (Dramis et al., 1993), emphasizes the socio- to fast moving and slow moving landslides in Italy, economic relevance of landslides, which often cause as obtained by hierarchic geomorphometric analysis heavy damage and loss of human life. Well-known (Bisci et al., 2002; Bisci et al., in preparation). catastrophic landslides in Italy were those of Vajont Deep-seated gravitational slope deformations (mainly (Müller, 1964), Ancona (Crescenti et al., 1983; lateral spreading and sackung phenomena) and large- Coltorti et al., 1985; Crescenti, 1986; Cotecchia, scale landslides are both frequent in Italy (Crescenti 1997), Valpola (Govi and Turrito, 1992; Dramis et et al., 1994). al., 1995) and Sarno (Celico and Guadagno, 1998;

Figure 1.1 - Distribution model of land susceptibility Figure 1.2 - Distribution model of land susceptibility to fast moving landslides in Italy to slow moving landslides in Italy (after Bisci et al., in preparation). (after Bisci et al., in preparation). Volume n° 1 - from PR01 to B15 n° 1 - from Volume

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi environmental regulations (Law n.365/2000,known provided in2000 bytheItaliangovernment withnew the assessmentofhydrogeologicalhazardinItalywas euros-worth ofdamage,asignifi causing alarge numberofvictimsandover 50billion Soverato 2000,Piemonte-Valle d’Aosta2000,2001), decade (Piemonte1994, Versilia 1996,Sarno1998, and landslideevents whichstruckItalyinthelast After theheavy sequenceofcatastrophicfl on Vulnerable Areas). distribution atanationallevel (AVI -ItalianProject 1991-1992, afi inhabited centersaffected bylandslidesand,in which, inturn,launchedaresearchprogramon the DefenseagainstHydrogeologicalCatastrophes, Civil ProtectionconstitutedtheNationalGroupfor Conservation) started;in1985,theMinistryof research project“Conservazione delSuolo”(Soil activity inthisfi of Civil Protectionbroughtafurtherincreaseof and, inthe1970s,constitutionofMinistery Protection againstHydrogeologicalHazard(IRPI) Council (CNR),createdfourInstitutesforthe acknowledged: inthe1960s,NationalResearch geo-environmental hazardshasbegan tobefully However, onlyinrecenttimestheimportanceof builders tothenationalcommunity. transferring offi of building regulations, have simplyresultedinthe Moreover, therepeatedamnestiesforinfringements constrains, oreven withoutany legal permission. the ignoranceofany possiblegeo-environmental and building activities, many ofthemcarriedoutin many cases,theresultofrecenturbandevelopments mistakes madeinancienttimes,but are,infact, in these inappropriatelocationsare,onlyinpart,dueto by recurrentdebris/earth/mudfl dormant landslidebodiesoralluvialfans built up are locatedinareaswithhighhazardlevels, suchas In fact, urbansettlements,villages,orsinglehouses compulsorily evacuated. offi and residents.In1970,1804inhabitedcenterswere urban settlements,withasignifi catastrophes. A large numberoflandslidesinvolve 32% ofthetotalamountvictimscausedbynatural from 1945to1990,landslideskilled2447people, to areportissuedbytheMinistryofPublic Works, may beestimatedin1000-1500€peryear;according The damagecausedbylandslidesandfl Guadagno cially listedasunstable,and304ofthemwere et al. rst systematic analysisoflandslide , 2000). nancial responsibilitiesfromthe eld; afew yearslater, theCNR cant riskforbuildings ow. The reasonsfor cant contribution to oods inItaly ooding Carton al Colombetti areas andfuturehazarddevelopment areas. hazard, inordertoassesstherisklevels ofbuilt-up to producedetailedmapsoflandslideandfl rainfall andfl recurrence (30,50,200years)modelsoftriggering resources toproducelandslideinventories, aswell River Basin Authorities have invested fi as the“ (Oddone, 1930;Cotecchia were triggeredinconnectionwithearthquakes and directobservation, alarge numberoflandslides As testifi 1985). of earthquakes (Ritsema,1970;Favali andGasparini, extensional tectonics,asproved byfocalmechanisms present, mostofthepeninsulaisstillinvolved in et al. 1985; DramisandSorriso-Valvo; 1994;Dramis deformations (Sorriso-Valvo, 1979;Dramis on hardbedrock,deep-seatedgravitational slope to landslideactivation. Inhighreliefareas,modeled narrow deepvalleys withhigh-steepslopes,favorable a generaldeepeningofrivers hasoccurred,generating et al. a moregeneralizeduplift(Dramis,1992;D’Agostino Pleistocene, theItalianpeninsulahasbeeninvolved in escarpments areconnected.StartingfromtheLower intramontane tectonicdepressionsandwidefault this latterproducedblockmorphostructurestowhich was followed bybothupliftandextensional tectonics; from the Tyrrhenian tothe Adriatic sea. This phase latter mainlyduringtheMiocene-Pliocene,migrating were formed.Compressionaltectonicsaffected these from UpperOligocene–Miocene,the Apennines during theCretaceous-Eocene;successively, starting tectonic units.Mostofthe Alpine beltwas formed chains werebuilt upbythe superimpositionofvarious originated the Alps andthe Apennines. Boththese the resultofevents which,inconsecutive phases, The geologicalsettingofItalymostlyrepresents The geologicalframework induced bypastclimates. weathering, erosion,andsedimentationprocesses Landslide susceptibilityisalsolargely affected by activity Quaternary climatesandhuman ., 1982;Crescenti , 2001;Bartolini , 1995),werealsofrequentlytriggered. At et al. Decreto Soverato ed byhistoricaltestimonies,oraltraditions, et al. , 1987;PrestininziandRomeo,2000). ooding events. These dataareused , 1979;Cotecchia,1981;Dramis et al. et al. , 1984;D’Elia ”). Inthiscontext, several , 2003). As aconsequence, et al. , 1969;Govi, 1977; et al 24-05-2004, 15:25:36 nancial ., 1985; ooding et al. et , LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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uplift, to deepen in the bedrock, thus inducing slope instability. Many of the large scale landslides owe their fi rst activation to the Holocene deepening of river channels (Dramis et al., 1992). Some of them show a step-like evolution, with short reactivation phases separated by long periods of inactivity. Postglacial alluvial fi lling of valleys largely stabilized those movements during the Holocene (Cotecchia, 1978). After the retreat of Pleistocene glaciers, along the Alpine arc, conditions particularly favorable to landslide activation were established; the lack of lateral support to slopes originated collapses in moraine materials and in the bedrock, especially when this latter was fractured by tectonics and deformed by ice pressure (Panizza, 1973). Presently, similar phenomena are still very frequent, often representing high hazard situations. Moreover, in recent years, the role of degradation in triggering landslides in high mountain areas has been pointed out (Zimmerman and Haeberli, 1998; Dramis et al., 1995; Harris et al., 2003). Minor phases of erosion and fi lling, connected with climatic variations which occurred in historical times, also infl uenced landslide activity (Veggiani, 1981). Human activity, which for a long time has been modifying the Italian territory, plays a primary role in landslide triggering (Canuti et al., 1979). Both modifi cations of slope geometry (due to earthworks, mining, and construction), and local enhancement of pore pressure in bedrock and overburden materials (due to water infi ltration into the ground from water pipelines and sewerage leakage), are responsible for widespread slope instability in hilly areas (Dramis Figure 1.3 - Distribution of the main lithological et al., 1993). Very recent river bed deepening, complexes in Italy sometimes up to more than 10 meters, connected to both quarrying into river beds and other human During the Quaternary, climatic changes, along with activities such as dam construction, reafforestation uplift, produced successive conditions favorable etc. (Cocco et al., 1978; Conti et al., 1983) have and unfavorable to river valley deepening, thus triggered (or reactivated) several landslides (Dramis establishing different slope stability conditions. et al., 1979). The reduction of vegetation cover, connected to cold and arid climates, favored soil erosion and Geological factors of slope instability The occurrence and frequency of different types

physical weathering; slopes were therefore covered PR01 to B15 n° 1 - from Volume by thick debris layers, moving downwards by rill of landslides are closely related to the mechanical erosion and superfi cial mass movements. Overloaded properties of the outcropping rocks and eluvial- river water produced thick alluvial fi llings, thus colluvial materials. stabilizing slopes. New vegetation covers, connected Taking into account landslide susceptibility, eight with climatic amelioration, retarded soil erosion, main lithological complexes may be recognized allowed fl uvial water, no longer loaded, to incise the (Figure. 1.3). previously-deposed materials and then, continuing the a) Magmatic and metamorphic rocks

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi previous complex, whilemarly-clayey units,which situation very similar totheonedescribedfor planes canbegenerated.Lithoidmaterialsshow a occurrence ofclayey interlayers alongwhichshear lithological characteristics,jointing,structure,and argillites. Their stabilitycanvary accordingto siliceous limestones,marlymarls,and lithology rangesfrommicriticlimestonestojaspers, This complex ismadeofstratifi d) Calcareous-marly-silicic rocks clays) (Manfredini affected bylateralspreadingphenomena(e.g.siltsand the edgesofhardrockslabsoverlaying soft rocks,and and fault escarpments). They arealsofrequentalong slopes (suchas,deepnarrow valley sides,coastalcliffs structure. Suchphenomenaarecommononhighsteep block-slides, whosegeometryisstronglycontrolledby joint sets,andarelocallyaffected byrockfalls and These rockareofteninterestedbyclosely-spaced c) Massivecalcareous rock long-lasting rainfalls orearthquake shocks. sudden accelerationsasaconsequenceofheavy and evolve slowly, even thoughthey canexperience toes), arewidespread. These phenomenagenerally transition intoslow moving mud/earthfl translational landslides,(whichoftenmake the slopes. There rotational landslidesand,lessfrequently, frequency oflandslide,even over gently dipping properties. Therefore, thiscomplex shows thehighest structure, worsening theiralreadypoormechanical deformations, whichdeeplydisturbedtheiroriginal affected bytectonicandtectonic-gravitational are widespreadallalongthe Apennines) werestrongly During geologicaltimes,theseclayey rocks(which b) Caoticandundifferentiated formations involved inrotational andtranslationalslides. Mountain slopesmodeledinschistsarelocally escarpments toes. causes theemplacementofthicktalusdepositsat et al. Prestininzi, 1979;Sorriso-Valvo, 1979;Crescenti slope deformationsarefrequent(Genevois and rock slides/avalanches. Onhighslopes,deep-seated exception ofrockfalls (onescarpments)and(local) involved ingravitational phenomena,withthe to weathering. They aregenerallyonlymodestly make theserocksreactdifferentlycompositions Different mineralogicalandpetrographical , 1994). At highelevations, frostshattering et al. , 1980). ed units, whose ows attheir et al. et al. colluvial covers ofhillslopes(Bertini moving earth/mudfl evolving intomudfl bedrock andeluvial-colluvialcovers, and often Rotational andtranslationalslides,affecting both been upliftedtoaminorelevation. latter depositsnormallyconstitutelow hills,having only bythemorerecentextensional tectonics. These consolidated orlooselacustrinematerials,affected to sometimeshighelevations, aswellscarcely affected bythelatestcompressive phasesanduplifted This groupgathersconsolidatedclayey terrains, f) Pliocene-Pleistocenemainlyclayey deposits areas, translationalandrotationalslidesarenotrare. earth fl cemented formationsareoftenaffected byslow mud/ Reliefs modeledinOligocene-Miocenescarcely- may occuronsteepslopesandescarpments. lithotypes aremuchmorestable,even thoughrockfalls areas stronglyaffected bytectonicactivity. Arenaceous are frequent,mainlywherepeliticfacies prevail, andin layers. Also, rotationalslidesandslow earth/mudfl presence ofpressuredwater withinthearenaceous translational slidesfrequentlyoccur, beingfavored by fact, constitutepotentialslippingsurfaces alongwhich alternations ofsandyandclayey layers;theselatter, in geomorphological setting.Particularly unstablearethe according toslopelithology, structure,and Landslides arefrequent,varying intheirtypology high reliefsandsteepslopes,isgenerallyfound. cohesion. Connectedtothem,aroughlandscapewith of materialsdiffering inlithology, grainsizeand The unitsofthiscomplex aremadeupofalternations deposits Scarcely cementedOligocene-Miocenemarine e) Flysch andcalcareous-marly-sandy turbidites. agricultural activity. wash processesandalsobecauseof,morerecently, during pastcolderperiodsbysolifl by landslides. Those lattermaterialsweremobilized meters thick,appeartobemorefrequentlyaffected are oftencovered byweatheredmaterialsuptoseveral (Crescenti deformations andlarge-scale landslidesarepresent Adriatic andIoniancoastalcliffs, deep-seated slope modeled onarenaceous-conglomeratic. Along the 1986). Rockfalls locallyaffect theedges ofscarps , 1995). , 1985;DramisandSorriso-Valvo, 1994;Dramis ows, even though,especially inhigherrelief et al. , 1983;Cancelli ows widelyinvolve theeluvial/ ows, arewidespread. Slow- et al. uction andslope , 1984;Coltorti et al. , 1984and 24-05-2004, 15:25:18 ows LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

TEMPORAL EVOLUTION, AND IMPACT ON HUMAN SETTLEMENTS B08

Figure 1.4 - The landslide affected towns which will be visited in the fi eld trip.

sometimes leaning against slopes, sometimes being terraced or constituting valley fl oors and plains. Their stability is strictly connected to their physical characteristics, to those of the underlying bedrock and, most of all, to their morphological position. In higher relief areas, different types of gravitational phenomena (mainly slides, debris avalanches and, most of all, debris/ earth/mud fl ows) occur (more frequently over crystalline bedrocks), mostly in connection with exceptional meteoric and seismic events. Very frequent are fast-moving landslides which affect moraine deposits, mostly when they overly metamorphic schist rocks. In densely-populated Alpine valleys, debris fl ows and debris avalanches can assume a catastrophic character, also because built-up areas are often located at the mouth of deep gullies along which the debris moves down (Dramis et al., 2002). Minor gravitational movements (soil slips) affecting mainly shallow eluvial and colluvial materials along mountain slopes are widely triggered by heavy and prolonged rainfalls (Govi et al., 1985).

g) Recent and present volcanoes, with their lavas and The Field Trip pyroclastic rocks The fi eld trip will include fi ve excursion days (August These rocks have very different characteristics, 15-19), from Valmontone (30 km south of Rome) to varying from dense massive lavas (sometimes closely Florence (Figure. 1.4). During this period, a number fractured by tectonics or cooling), to loose tuff layers. of huge landslides affecting urban settlements Quaternary pyroclastic layers are particularly affected will be visited, The fi rst trip day will examine the by various types of landslides, especially where they towns of , Calitri, and (in , overlay clayey materials (e.g. withdrawal phenomena Region), deeply involved in gravitational affecting the borders of thick tuff slabs (Tommasi movements triggered by the November 1980 et al., 1986; Conversini et al., 1995). A particular Southern Italy earthquake. The second day topics condition of instability, due to the presence of will be those related to the unstable towns of Craco, quickly weathered and scarcely coherent pyroclastic Campomaggiore, and Ferrandina, in the Bradanica materials overlying steep lithoid slopes, can generate Trough (Basilicata Region). The third day will start extremely dangerous earth/mud fl ows (Celico et al., with a visit to the archeological roman settlement of PR01 to B15 n° 1 - from Volume 1986; Guadagno, 1991; Celico and Guadagno, 1998; Pompei, buried by the Vesuvius eruption of 79 A.D., Guadagno et al., 2000). followed by a scientifi c stop in the area of Sarno, struck by catastrophic mudfl ows in May, 1998. On h) Pleistocene, Holocene and present superfi cial the fourth day, two huge landslides mobilitating the deposits urban settlements of the Marche Region (Ancona, These materials are very heterogeneous in grain size on the Adriatic coast, and Montelparo, in the peri- and clay content; also their distribution is quite various, Adriatic Plio-Pleistocene hilly belt) will be examined.

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi affected bylandslidemovements. Region), whoseperimetralescarpmentsareheavily examining thehistoricaltown ofOrvieto(Umbria Finally, thelastdaywillbecompletelyspentin Fifth Day Fourth Day Third Day Second Day First Day Field tripschedule -8a.m. Transfer bybus from Valmontone excursion. Transfer bybus toFlorence-end ofthe Lunch inOrvieto. Dinner andovernight inOrvieto. Ancona. Lunch ontheroad. Montelparo. Tronto. Dinner andovernight inS.Benedettodel Sarno. Lunch atPompei. Visit tothearcheological siteofPompei. Benedetto del Tronto. Dinner andovernight inPompei. Ferrandina. Lunch ontheroad. Craco. Campomaggiore. Pompei. Dinner andovernight inPotenza. Senerchia. Calitri. Lunch ontheroad. Bisaccia. Irpinia-Potenza. (Rome) -Centro diEccellenzaCERIto -8a.m.Orvieto -8a.m. Transfer bybus toSarno-S. -8a.m. Transfer bybus toOrvieto. -8a.m. Transfer bybus toBradanica- Cotecchia earthquakes inItaly(see,forexample, Oddone,1930; very large gravitational movements triggeredby Several historicrecordsandoraltraditionsexist of F. Dramis Introduction November 1980Southern ItalyEarthquake Gravitational Phenomena Triggered bythe From Valmontone (Rome)toPotenza Field itinerary of earthquake-related landslides( seated gravitational movements), atypicalfeature shallow groundfailures, tohuge landslidesanddeep- any kindanddimension (rangingfromvery smalland Even thoughearthquakes cantriggerphenomenaof dormant orevolving atavery slow rate. characterized byinstability, but whicharenormally mass movements mayinvolve slopesalready It hasalsobeenpointedoutthatearthquake-triggered being carriedoutthroughouttheItalianterritory. Canuti formations” hastobestressed(Cotecchia,1978; importance ofidentifying“engineeringgeological As far as lithologicalfeaturesareconsidered,the fracturing andfaulting). connected withotherseismicgroundeffects (suchas many earthquake-induced massmovements arealso intensity (Arias,1970).Ithasalsobeenoutlinedthat characteristics oftheshock,particularlywith Arias related tobothlitho-structuralfeaturesofthesite,and dimension oftriggeredmassmovements arestrictly to understand(Keefer, 1984)thatthetypologyand records oftheshock.Inthisway ithasbeenpossible earthquakes, alsocomparingthemwithinstrument with morescientifi In recenttimesithasbeenpossibletosurvey directly, 1982; Crescenti which generallyreactivate onlyasaconsequence et al. , et al. B. Gentili , 1988);researchtothisendispresently et al. , 1969;Govi, 1977;Dramis c methods,surface effects ofstrong , 1984). , DAY 1 G. Pambianchi i.e. ofphenomena 24-05-2004, 15:25:23 et al , LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

TEMPORAL EVOLUTION, AND IMPACT ON HUMAN SETTLEMENTS B08

Figure. 2.1 - Earthquake-induced ground fracture in the area (after Dramis et al., 1982, modifi ed)

1987), heavily involving a wide portion of the Campania and Basilicata regions, even though it was registered (up to III MCS) in a large part of the Italian peninsula. The earthquake, whose macroseismic intensity in the epicentral area was estimated at around IX-X MCS, produced widespread and severe damage, about 4000 casualties and many injuries. The source was a dip-slip normal fault with Apennine (NW-SE) strike and SW dip, towards the Tyrrhenian Sea. The focus was some 18 km deep. The shock was, in many aspects, similar to those affecting more or less the same area in 1930 and 1962. Co-seismic surface faulting was recorded in the area (Cinque et al., 1981; Bollettinari and Panizza, 1981; Pantosti and Valensise, 1990) as well as vertical movements (Cotecchia, 1982; Arca and Marchioni, 1983). Widespread were surface fractures, both isolated or joined of strong seismic shocks) is their wide extension in groups (Figures. 2.1–2.2), up and elevated depth. These kind of mass movements, to several kilometers long. Theyw being activated only by extreme events (mainly strong opened in a variety of lithologies earthquakes and, subordinately, intense rainfalls), (including loose superfi cial typically show recurrent activity, alternating long material, such as alluvial deposits Figure 2.2 steady periods with sudden reactivations. and inactive landslide bodies) Earthquake Among earthquake-induced surface effects, lateral as a consequence of interference induced ground fracture, cutting spreadings, causing progressive “graben like” sinking between seismic, tectonic and a house on hill tops, are reported (Solonenko, 1977; Dramis gravitational stress (Carmignani et et al., 1983). al., 1981; Dramis et al., 1982) Very important for the activation of landslides (and, Many of these discontinuities opened as a reactivation of course, of earthquake-induced ones, too), are of fractures created by past earthquakes (e.g. in 1930 also hydrogeological conditions (such as saturation and in 1962), as reported by several authors (Alfano, of terrain, variations of piezometric level etc.). 1930; Oddone, 1930; Vari, 1930; Serva, 1981). Their Particularly frequent on saturated sandy-silty opening frequently lead (both in 1980, and during sediments are liquefaction phenomena which can past earthquakes) to gas emission (and, sometimes, produce instability either directly (because of fl ow ignition). slides along saturated sandy-silty slopes) or indirectly Along some of them, a sharp increase in the helium (by allowing the mobilization of overlying terrains). content of the soil has been recorded (Dramis et al., These kind of landslides (Tinsley et al., 1985) often 1982), that may indicate their depth (or at least their Volume n° 1 - from PR01 to B15 n° 1 - from Volume involve deep-seated beds too, disturbing very large connection with deep-seated crustal levels). areas far away from the epicenter. However, the most outstanding phenomena triggered by the earthquake were mass movements of different The 1980 Southern Italy earthquake types (Cantalamessa et al., 1981; Cherubini et F. Dramis, B. Gentili, G. Pambianchi al., 1981; Cotecchia, 1981, 1982; Genevois and A strong earthquake (M = 6.8-6.9) struck southern Prestininzi, 1981; Agnesi et al., 1983; Crescenti et Italy in November 1980 (Westaway and Jackson, al., 1984; D’Elia et al., 1985; Bisci and Dramis, 1993;

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Volume n° 1 - from PR01 to B15 B08 - B08 Figure 2.3-Thetown ofBisaccia. Leaders: F. Dramis,A.Prestininzi Immediately downslope ofthisdepression, there Varicolori) ofLateMioceneage. allochtonous clays(Varicoloured Clays - Argille conglomerate (Pliocene),overlying stronglydisturbed like platformmadeupofa50mthickpolygenic MCS intensity). This town isbuilt upover aterrace- the epicenter(theearthquake herereachedonlya VII of Bisaccia(Figure.2.3),locatedquitefar away from (Crescenti etal.,1984)thatinvolved mostofthetown southern Italyearthquake was thedeep-seatedsliding An importantmassmovement triggered bythe1980 F. Dramis The Bisaccialandslide Dramis et al. the above describedgroundfractures (Cantalamessa These movements oftenappeared to beconnectedwith the seismicevent). terrains (duetoheavy rainfall inthedayspreceding outcropping rocksandthehighwater contentofthe area, thepoorgeotechnicalpropertiesofmost partially determinedbythequitehighreliefof Dramis andBlumetti,inpress). They were,atleast, were massmovements on Tertiary fl Gregorio Magnoetc.).Morefrequentandwidespread , Valva, Bella-MuroLucano,Balvano-San close totheepicenter(suchasatCastelgrande, Calcareous formationswerelocallymobilized,quite of landslidesactivated bypastearthquakes. a shortperiod;mostofthemrepresentthereactivation after theearthquake, andtheiractivity lastedonlyfor gravitational phenomenamainlymoved immediately Balvano, ,etc.). (such asatBisaccia, Avigliano, Tricarico, Accettura, Lucano etc.)andonPliocene-Quaternarydeposits Laurenzana, Sant’AngeloleFratte, , Oliveto , 1981;Genevois andPrestininzi,1981; et al. , B. Gentili , 1982;BisciandDramis,1993). These , G. Pambianchi ysch (suchasat . is a13 complete destruction. The mostrelevant disruptive underlying conglomerateblocks,withoutsuffering artifacts weresimplytiltedtogetherwiththe extreme, even ifwidelydiffused. In fact, many Damage tothebuilt-up areawas generallynot 1962). after theprevious strongearthquake events (1930and carried outbymunicipalitytechniciansimmediately as clearlytestifi reactivation intheoccasionofpastseismicevents, been recognized. They have experienced recurrent the margins of theconglomerateblocks,have fractures andscarplets,mostlycorrespondingto All alongthehistoricalcenter, coseismicground at itsbase(Crescenti as wellthatofthehighescarpmentandtrench platform intoblocksmoreorlessturnedcounterslope process causedthefragmentationofconglomerate lateral spreadingprocess. This complex deformation rotational slide,withinamassinvolved inaslow, can beinterpretedasthatofadeep-seatedmultiple The geomorphologicalframework ofthetown area fragments nearthebottombyexploration boreholes. are quiterecent,astestifi the clayey substratum,ispresent. The fi 2.5). At itsfoot,a20mdeeptrenchpartlyoverlying the modernsector(inupperone)(Figures.2.4- parts: thehistoricalcenter(inlower sector)and A 40mhighescarpmentdivides thetown intotwo platform, counterslopesanddepressionsarefrequent. On theclayey slopesborderingtheconglomerate conglomerate bedrockandstronglytiltedupslope: area. All ofthemcanbeinterpretedaslandslidescarps. side). Minorescarpmentsarevisiblewithinthebuilt-up Figure 2.4-Thehighescarpmentwhich dividestheold town fromthemodernone(outofpicture,onleft th centurytower, deeplyemplacedinthe ed bydetailedmapsofsurface effects et al. ed bythefi , 1984). nding ofmasonry lling materials 24-05-2004, 15:23:16 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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effects occurred in connection with the earthquake reactivated ground fractures and scarplets (Figure. 2.6) and all along the edges of the conglomerate platform, where a number of buildings collapsed, as a consequence of local falls and slumps. Visit itinerary The visit to Bisaccia will include: Stop 1: General view of the town from the west (New Bisaccia-Piano Regolatore locality). Stop 2: Observations on damaged buildings within the main trench at the escarpment which divides the modern town from the historical one. Stop 3: Walk in the historical center to see the earthquake- triggered ground fractures, scarplets and the related damage. The landslide complex of Calitri M. Del Prete The town of Calitri lies in the Southern Apennines on Figure 2.5 - Schematic geomorphological map the left bank of the River valley, about 100 km of the Bisaccia area. Legend: 1. “varicoloured clays”; 2. conglomerates; east of Naples. 3. debris; 4. main landslide escarpment; 5. edge of The bedrock of the built-up area consists of sands in the conglomerate platform scarp retreating by mass lenses within the upper parts of the Blue Clays (Argille movements; 6. stream erosion; 7. trench; 8. minor Azzurre) siltites, in which further, olistostromic landslide scarps and fractures reactivated lenses of more plastic, Varicoloured Clays (Argille by the November 1980 earthquake Varicolori) occur. The slope where the town is placed (after Crescenti et al., 1984, modifi ed). has an average inclination of approximately 10°, its relief is 245 m from the top (595 m a.s.l.) to the foot (350 m a.s.l.) close to the river. The bedrock layering dips 20°-30° eastward and is signifi cantly affected by tectonic disturbances. The Ofanto River fl ows approximately in the same direction. Therefore, its left valley side consists, in broad terms, of ridges of sand alternating with zones of clay, forming side valleys. The landslide complex which affected Calitri (Figures 7-8) occupies one of these side valleys. The Quaternary history of this part of the Ofanto PR01 to B15 n° 1 - from Volume valley, and in particular that of its river terraces, has been investigated by Del Prete and Trisorio Liuzzi (1981). Remnants of high terraces are present on both sides of the valley at various elevations. The present fl ood-plain terrace on the left bank of the river below Calitri is located at around 360 m a.s.l., Figure 2.6 - Damage along a reactivated scarplet. and has been partly overridden by the mudslides

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi . amajor, deep-seatedslide,withavolume of 1. Currently, fourmainelementscanbedistinguished: these observations. on Figure.2.8representasimplifi by DelPrete. The slidescarpsandboundariesshown photographs (taken in1974andDecember1980) mapped onthegroundandfromvertical stereoaerial as scarps,cracks,andshears)have beencarefully Surface featuresproducedbythemovements (such complex ofpre-existing oldslides(Figures2.9-2.10). predominantly ofthereactivation ofpartsa with theNovember 23,1980earthquake consisted The landslideswhichaffected Calitriinconnection 760 mmover theperiod1930-1972. precipitation attheCalitristationhave averaged about 500 mdownstream. The available dataonannual around 400-410ma.s.l.onthesameriver bank,about complex. A fragmentofanearlierterraceislocatedat which formthelower elementoftheCalitrilandslide affected bythenorth-northwestern secondaryslide 2 minthatvicinity. Inthenew partofthetown, the eventual, near-vertical displacementsof1to these cracksproceededforseveral hourstoproduce movements ofthegroundonsouthernside main earthquake shock,andthatslow downward main rear(scarpR,2..8)ataboutthetimeof the oldtown, cracksappeared onthelineof April 1982was that,atleastinthemainsquareof impression wereceived fromourdiscussionsin out becauseoftheprevailing panic. The limited of theseevents doesnotseemtohave beencarried thorough andpromptexamination ofthewitnesses about 7.35p.m.,localtime)andpartlybecausea partly becausetheearthquake struckafterdark(at listed massmovements isincomplete. This maybe Information onthetimingsanddurationsofabove shallow translationalmudslides,whichform 4. shallower slidesinthesteepertoeareaof 3. associatedsecondaryslidesaroundtherearscarp 2. the orderof20x10 into theleftsideofriver. mudslides areabout10mthick,andprotrude to theRiver Ofanto. The active partsofthese part ofthecolluvialapronextending down the following massmovements; main slide,whichsupplymaterialtotheheadof north-northwest (2b)ofthemainslide; are thosewhichextend north-northeast(2a)and of themainslide(1);these,mostimportant town anditstoe55to75mabove river level; vertical height),withitsrearscarpintheold two-thirds ofthevalley slope(ca.240mintotal 6 m 3 , occupying theupper ed summaryof sliding body)are2/3and360m,respectively. taken forKandBe(breadthofequivalent rectangular 2.1. Inthethree-dimensionalanalyses,values r calculations werecarriedoutforarangeofassumed acting ontheslipsurface was poorlydefi Hutchinson, 1969). As thepiezometricpressures used withoutinvolving large errors(Skempton and about 0.14:theConventional Methodcouldthusbe the mainlandslide,depth/lengthratio(d/L)was the mainlandslideandmudslideatitsfoot.For preliminary stabilityanalysesweremadeonboth Despite theseveral uncertaintiesoutlinedabove, 2.8), whichwerenotreactivated bytheearthquake. slides, lieareasofoldslidesandmudslides(Figure. Beyond theboundariesofabove-mentioned active same typeasthefi suggested previously, slide2bmayhave beenofthe essentially completedwithinabout24hours. As secondary slides(2aand2b)appeartohave been Signifi produced avertical scarpabout0.8mhigh. midnight thesubsidenceofheadthatslidehad appeared atabout8.00p.m.,localtime,andthatby (2b, above), theevidence suggeststhatthefi level), 0.36and0.24. The value of water level coinciding,onaverage, withground kN/m taking c’ assuming thatitswinterfactor ofsafetyis1.0and the mainlandslide,onslipsurface RT (Figure.2.8), results ofvarious back-analysesofthestability in additiontotheusualtwo-dimensional ones. The three-dimensional stabilityanalyseswerecarriedout slide ofroughly0.6,anditsconsiderabledepth, of thefairly low breadth/lengthratio(B/L)ofthis appropriate touseresidualshearstrengths.Inview of movement onapre-existing slipsurface, itis main landslideandtheactive mudslideatCalitri. Tab. 2.1-Back-analyses ofthestability u value ofr Assumed .4 01 8.5° 10.2° 12.9° 10.1° 12.2° 0.24 15.1° 0.36 0.48 values, 3 cant movements ofthemainslide(1)andits . As the1980landslideinvolved arenewal r u =0,aresummarizedbelow, andin Tab. i.e. 0.48(approximatingtoawinterground- analysis dimensional Two- rst slide. ϕ ’ r requiredforF=1.0, with c’ r =0 with K=2/3 analysis, dimensional three- Approximate γ istaken as20.6 rst crack rst nd the ned, 24-05-2004, 15:23:23 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

TEMPORAL EVOLUTION, AND IMPACT ON HUMAN SETTLEMENTS B08 of the Calitri landslide complex. Figure 2.7 - Geologic-geomorphologic map Figure Volume n° 1 - from PR01 to B15 n° 1 - from Volume

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi dolomites andlimestonesofthePanormide Complex, Valley, onthe tectonicboundarybetweentheJurassic Senerchia liesontheright-handsideofupperSele some cases-threateningthetown. manifestations amongotherlandslides–latentin fringed thebuilt-up area,areonlythemostevident However, thesehugemassmovements, which 1980 earthquake (CotecchiaandDelPrete,1984). mudslide, whichwas reactivated following the One ofsuchinstanceistheSerradell’Acquara that extensive areasareaffected bymassmovements. the frequency ofearthquakes here,but alsotothefact The highgeologicalhazardisattributable notonlyto lives. inadequate buildings collapsedwiththelossofmany disjointed Quaternarydebrismaterials,allthequite southern partofthetown, constructedonfaulted and Lucania onNovember 23,1980.Especially inthe during theearthquake whichstruckCampaniaand geological hazard.Senerchiawas very badlyhit in aSouthern Apennine region characterizedbyhigh The town ofSenerchia( Province) issituated M. DelPrete The landslideofSenerchia View ofthemainlandslidetoe. Stop 3: Walk alongthemainlandslidebody. Stop 2: Stop 1: The visittoCalitriwillinclude: Visit itinerary of theearthquake-induced landslidemovements. introduction tothegeological-geomorphologiccontext General view ofthetown fromthefootballfi

Figure 2.8- A sectionalongthemainlandslideofCalitri. eld, and eld, calcilutites, andthin,generallybadly-shattered interbeds, suchasmarlylimestones,light-coloured consists of Varicoloured Clayswithsubordinaterocky affected bythehugeSerradell’Acquara mudslide:it The mainlyclayey part widelyoccursinthearea beds ofsandstone,marlylimestoneandlimestone. sequences of Varicoloured Clays,alternatingwith predominant; theother, instead,consistingofstratifi one ofwhichwiththepeliticcomponentdecidedly Unit canbedistinguishedintwo different parts: borehole logsinthisareaindicatethattheSicilide Ground surveys andinformationobtained from several dozencubicmetersinsize. produced macroscopiceffects, suchasmegablocks fl are sofi bedding almostcompletely. Indeed, therockmasses tectonic jointsthat,inmostcases,have obliteratedthe the SicilideComplex (Figure.2.9). The two complexes and theCretaceous-EocenepeliteFlyschUnitsof (after Bigietal.,1992). (Eocene-Upper Triassic) and subordinatedolomites 35: Shallow-water limestones Upper Cretaceous); 22a: SicilideUnits(Eocene- (Quaternary); deposits 10: Alluvial Senerchia area.Legend: geological mapofthe Figure 2.9-Simplifi oury appearance. The fracturingofbedrockhasalso nely fragmentedthatthey frequentlyhave a ed widespread networks of to extensive andvery have beensubjected These rocksasawhole calcareous dolomites. limestones and made ofdolomitic Panormide Unitis In thisarea,the Sele Valleygraben. downthrown inthe by theSicilideUnits tectonically overlain Panormide limestones, the deepestbeing allochthonous units, form superimposed 24-05-2004, 15:23:28 ed LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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sandstone beds. reactivation of a landslide mass that had lain quiescent Lying right up against the tectonic contact between for at least 40 years, as confi rmed by the age of the 29 the limestones and the Sicilide Unit, is the Quaternary rural houses destroyed. It could well be, however, that detrital slab on which Senerchia was built. This slab the slide had remained quiescent even longer than the can be considered as an accumulation of fault breccia, period indicated by the age of these houses. Indeed, talus, and hillside wash. The slope which has provided it would be more reasonable to go back to the 1930 the detrital material over a long geological period is earthquake. Though there is no certain proof of the bounded by a fault running along the eastern side of veracity of this assumption, it is supported by the the Mt. Cervialto limestone horst. recollections of some of the older local inhabitants. The Serra dell’Acquara mudslide, reactivated by What is certain, however, is that no appreciable the 1980 earthquake, is one of the largest mass remobilization occurred over the last forty years, movements in the whole earthquake-stricken area. even following periods of very heavy rain. This fact It fringes the built-up area, running along a fault line is certainly borne out by the survival of numerous old which separates the Sicilide Unit from the detrital slab houses along the whole length of the slide, and the on which Senerchia stands (Figure. 2.10). stories collected of past events.

Figure 2.10 - A section along the Senerchia landslide.

The particular weakness of the slope where the mass Following the main shock of November 23, 1980, the movement originated in geological time is attributable mudslide was gradually remobilized. The movement not only to the above mentioned tectonic discontinuity, started from upstream and slowly spread downstream, but also to the unfavorable hydrogeological situation over a period of a couple of weeks. The fi rst cracks found along the upstream tectonic contact between appeared in a secondary zone of depletion along the the carbonate aquifer and the Sicilide aquiclude. The Oliveto Citra road, which had to be closed. The Mt. barrier springs that occur here pour out enormous Stella aqueduct was also cut some fi fteen hours after quantities of water into the unstable basin below (200 the main shock, while almost at the same time the l/sec). main scarp was formed in the 475-490 m contour The shocks recorded on November 23, 1980, area. PR01 to B15 n° 1 - from Volume reactivated this 2500 m long, 500 m wide mudslide, As a result of these various events the long mudslide mobilizing an estimated volume of around 28 x 106 occupying the channel was slowly set in motion, and m3. The slip surface wholly lies in the pelitic Flysch started slipping downhill. The slide, formed of Sicilide of the Sicilide Unit at a maximum depth of 33 m, Clays overlain by broken masses of calcareous as indicated by borehole and nuclear logging data. breccias, exhibits very evident shear boundaries, thus Comparison of aerial photographs taken before indicating quite clearly how it was reactivated. In the and after the 1980 earthquake, clearly reveal the initial phase, the material slipped almost as a single

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi the infi Tab. 2.2.Resultsofback analysis using the two- andthree-dimensionalanalyses. at adepthof25m. Table 2.2setsforththeresultsof method, sincethetopographicsurface iswelldefi run onthemudslidechannel,usinginfi Back analysis,atlimitequilibriumconditions,was thus occurredaboutonemonthafterthemainshock. exceeded. Remobilizationoftheaccumulationzone created whenthesuperiorequilibriumlimitstatewas precisely herethatvery evident failure surfaces were uplift ofaround20m,alongthelinecontact.Itis the pre-existing zoneofaccumulation,causingan superimposed, eventually cametoexert pressureon movements ofremoulded,muddymaterialwere The mainmoving mass,onwhichlocalsecondary without beingdestroyed. houses standingthereonwereshiftedseveral meters mass, ascanbededucedbythefact thattreesand geomorphological context. side, andgeneraldiscussiononitsgeological- General view ofthelandslidefromitsleft Stop 1: itinerary: The visittoBisacciawillincludethefollowing Visit itinerary Close view ofthemainlandslide scarp. Stop 3: Stop 2: historical centerofSenerchiaisfounded. Close view ofthecalcareousbreccias onwhichthe . 01) 82 7.9° 9.0° 10.4° 8.2° 12.5° 9.3° 15.5° 10.8° 0.2 (0.11) 13.0° 0.4 (0.22) 16.0° 0.6 (0.33) 0.8 (0.43) 1.0 (0.54) of m(r value Assumed nite slopemethod u )

analysis dimensional Two-

ϕ ’ r withc’ requiredforF=1.0, with K=2/3 analysis, dimensional three- Approximate r =0 nite slope nite ned consist ofinterbedded,illite-smectiteandabundant strength. The claymineralswhicharetherepresent, materials, beingcharacterizedbyalow shear The varicoloured claysare the mostunstable varicoloured clayssandwiched betweentheslices. Flysch, whicharerelatively morerigid,withthe arenites andmarlsmarlyclaysoftheNumidian imbricated seriesofslicesformedbythequartz- A successionoftectonicevents hascreatedan limestones, marlyandcalcarenites. of claysandmarlyclays,withintercalations of probableUpperCretaceousage.Itconsistsmainly the Varicoloured ClaysComplex (SicilideComplex) The FlyschComplex isheretectonicallyoverlain by limestone orpredominantlyofsandstoneinterbeds. consists ofclayey-sandy alternations,sometimeswith The SerraPalazzo Formation (Langhian-Tortonian), arenite member, withthininterbedsofmarlyclay. arenites andcalcarenites),amainlyquartz- (alternations ofdark-grey marlyclayswithquartz- (Langhian), consistsofaclayey-sandy member marls, andclays. The NumidianFlyschFormation alternations oflimestones,marly and calcarenites,withmoreorlessclosely-knit Formation (Aquitanian)consistsofcalcirudites (Argille Varicolori) Complex. The RedFlysch Palazzo formations),andthe Varicoloured Clays the RedFlysch,NumidianandSerra complexes outcrop:theFlyschComplex (including In theCampomaggiorearea,two lithological M. DelPrete The LandslideofCampomaggiore From Potenza toPompei Field itinerary View ofthelandslidetoe. Stop 4:

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TEMPORAL EVOLUTION, AND IMPACT ON HUMAN SETTLEMENTS B08 Figure 3.1 - Geomorphologic sketch of the Campomaggiore area. 3.1 - Geomorphologic sketch Figure Volume n° 1 - from PR01 to B15 n° 1 - from Volume

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi slowly asaunique houses, moved down time includedca.250 village, whichatthat 10, 1884,thewhole the nightofFebruary chronicles, during by thecontemporary Vecchio.reported As of Campomaggiore reactivation was that case oflandslide A noteworthy in theupslope. instability conditions small valley-induced erosion ofthelower far asthebackward This evolution hasrepeatedlyoccurredover time,as slides, causingthedisruptionoflandslidebodies. which prevented afreerapidevolution oftherotational (Serra Palazzo Formation), actedasa narrow neck, left onemadeofsticky marly-arenaceousalternations quartz-arenites (NumidianFlyschFormation), andthe The smallvalley withitsrightsidemadeofstiff was incautiouslyfounded. over whichthevillageofCampomaggiore Vecchio for theemplacementofwidelandslideterrace, related toalarge-scale rotationalslide,responsible escarpment following the550mcontourline,is they aredisplacedbymorerecentmovements. The are present. They appeartoberelatively old,since referable torotationalslideandfl Contessa localities),anumberoflandslidefeatures, upper partoftheslope(MontecrispoandCasinodella at Campomaggiore Vecchio (Figure3.1).Inthe movements whichinvolved the Varicoloured Clays and peculiarcharacteristics,arethegravitational Particularly interestingfortheircatastrophiceffects clays oftheNumidianFlysch. earthfl also rotationalslipsassociatedwithmudslidesand landslides. Inadditiontothesetranslationalslides, the former, andalongtherupturesurfaces ofprevious the Varicoloured Clays,alongthebedding planesof tectonic contactbetweentheNumidianFlyschand with tectonicphenomena. These slidesoccuronthe on suchalarge scalethatthey maybeconfused the mainfactors whichcausetranslationalslides The geologicalstructureandtheclayey bedrockare subordinate quantitiesofchlorite. smectite, withilliteandkaoliniteinfair quantitiesand ows affect thevaricoloured claysandthemarly o movements, ow the oldone. (the presentCampomaggiore),about3kmsouthof The villagewas evacuated andrebuilt onanew site in connectionwithheavy rain. local testimoniesreportedthatthelandslideoccurred installed later, in1889.However, fromoraltradition, reference meteo-station(thatofPotenza)was on thetriggeringrainfall, sincetheonlypossible Unfortunately, noreliableinformationisavailable out ofshapeandeven fragmentedintopieces. the railway stationtothevillagewas greatlypulled but notonecollapsed. Onthecontrary, theroadfrom Some buildings were damaged,moreorlessheavily, body, sothatnoinhabitantswerekilledorinjured. buildings. Vecchio toseethelandslideeffects onstructuresand Walk geomorphological context ofthearea. Nuovo andintroductiontothegeological- Panoramic view ofthelandslidefromCampomaggiore Stop 1: landslide willinclude: The visititineraryoftheCampomaggiore Vecchio Visit itinerary and Salandrellarivers. southeast, whichdivide thevalleys oftheBruscata a.s.l. onanundulatinghillyridgerunningnorthwest- The villageofCraco(Figure.3.2)islocatedat390m M. DelPrete(University ofBasilicata,Potenza) The LandslideofCraco

across thedisplacedvillageofCampomaggiore

Figure 3.2-ThevillageofCraco. 24-05-2004, 15:23:38 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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In the upper parts of the ridge, conglomerates and for the sub-vertical layering of the north-eastern conglomeratic sands of the Lower Pliocene age fl ank, and the low south-westward dip in south- outcrop, and transgressively overlay the Varicolored western fl ank. According to Lentini (1969), the Craco Clays (Argille Varicolori) of the Sicilide Complex Varicolored Clays and conglomerates belong to the (Cretaceous-Eocene). This older succession is in Metaponto Nappe, superposed on the Blue Clays of tectonic contact with the Blue Clays (Argille Azzurre) the Bradanica Foretrough. of Pliocene age, which outcrop in the middle and The southwestern slope of the hills at Craco may be lower parts of the slopes (Figure. 3.3). subdivided into three zones which are morphologically

Figure 3.3 - Schematic geological map of the Craco-Ferrandina area. Legend: 7: Marine and alluvial deposits (Quaternary); 13-14a: Undifferentiated terrigenous and marine deposits, calcarenites (Lower Pleistocene-Upper/Middle Pliocene); 22b: Sicilide Units (Eocene-Upper Cretaceous) (after Bigi et al., 1992).

The conglomerates with polygenic elements, well-differentiated by their geological constitution. which have a median diameter of about 10 cm, are The parts where the conglomerates outcrop, such as characterized by medium to high cementation. They between the crest and the 103 State Road, where most contain sandy beds and sandy lenses which, in some of the old Craco village is located, have a rocky aspect places, indicate the attitudes of the strata. The top of with vertical faces corresponding to fault or fracture the south-eastern hill is made of conglomeratic sands, planes. which pass laterally to conglomerates. The maximum Downhill from the 103 State Road, in correspondence thickness of conglomerates is about 30 m. with the Varicolored Clays outcrop, the slope angle The Varicolored Clays are represented by smectitic becomes very low, until the fault-scarp dividing the and kaolinitic clays, red, green, and grey in Varicolored Clays and the Blue Clays is reached; here color, including tectonically-disarticulated packs the slope angle suddenly increases. of Apennine Flysch units. The thickness of the Three ditches, originating near the contact between Varicolored Clays cannot be evaluated, due to the the conglomerates and Varicolored Clays, incise the generally chaotic assemblage. The Pliocene clays slope. In the outcropping area of the Varicolored have a typical blue color, and form very wide Clays, these ditches are large and open, but in outcrops surrounding the hill of Craco. They consist correspondence with the fault scarp, they become of heavily over-consolidated illitic clays, with some very narrow. Beyond the fault scarp, they assume the sandy and silty interlayers, which enable the indistinct typical aspect of ditches in “badlands” areas. stratifi cation to be locally observed. Three main landslides affect the Varicolored Clays of On the south-western fl ank of the hilly ridge, a the three valleys. These movements are very large and clearcut fault scarp divides the Pliocene Blue Clays have considerable similarity since: from the Varicolored Clays. The latter have a chaotic 1. the slip surfaces are essentially in PR01 to B15 n° 1 - from Volume attitude, and are covered by a rigid conglomeratic Varicolored Clays; cap, which is divided by faults and fractures into three 2. the crowns of the landslides reach the parts forming three adjacent hilltops with different conglomeratic cap; attitudes. Whereas the strata in the outer hilltops 3. the foot of each landslide is situated in the show small inclinations, those of the middle one are narrow part of the valleys in correspondence arranged in a narrow anticline fold. A fault running with the fault scarp. along the axial plane of this anticline is responsible The central of these landslides was instrumental in

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi the placingofsomemetersthicknessfi required quiteextensive leveling operationsincluding retaining wall. The constructionofthefootballpitch pitch was built onthelandslideterracedownhill ofthe period, apparentlyfreeoflandslideactivity, afootball supporting operationstothewall. In1954,afteralong 1931, whenitwas foundnecessarytocarryoutsome There arenootherrecordsoflandslideactivity until displacement ofabout20cm. the constructionofwall, itsuffered avertical of 18m. The recordsstatethatimmediatelyafter of whichwerereportedtobefoundedatadepth 3.5 m,andwas constructedwitharches,thecolumns Road fromthelandslide. The wall hadathicknessof of aretainingwall in1888toprotectthe103State The earliestreliablerecordsrefertotheconstruction area, includingthecentrallandslideofCraco. (or reactivation) ofthenumerouslandslidesin earthquake was stronglyinfl is highlyprobablethatthedamageassessmentof Pisticci areain1688,areunknown. Nevertheless it Mercalli Scale)earthquake, whichstrucktheCraco- The landslide-triggeringeffects ofthehuge(I=X width of40m. mentioned fault-scarp, thelandslidenarrows toa reaches amaximumwidthof400m. At thepreviously becomes very wide,withtwo laterallobes,untilit State Road.Downhill fromthesescarps,thelandslide with adestroyed wall, built in1888toprotectthe103 situated atanelevation of310m,incorrespondence which was constructedin1969-70. A thirdscarpis visible immediatelydownhill oftheretainingwall, from itstoe(Figure3.4). The completelengthof landslip, withavery longmudslideoriginating It shows thecharacteristicfeaturesofaretrogressive destroying theoldestpartsofvillageCraco. along theCracolandslides. Figure 3.4-Geologicalsection uenced bytheactivation second scarpis 356 ma.s.l. A an elevation of the village,at the churchof which reaches the highestof can beobserved, hill, threescarps the topof to be70m.From depth isestimated and itsmaximum is about1.1km, the movement ll inorderto

and thevillagewas totallyabandoned. two laterallandslideswerealsostronglyreactivated, ground downhill ofthewall exposed thepiles. The at itsextremity, whileasinkingofabout15mthe sank morethan2m.Itswesternwingwas sheared retaining wall suffered considerabletranslation,and and theseconddownhill fromchurch. The new Two large scarsopened,oneinGaribaldiSquare, the totalcollapseofinhabitedareatookplace. movements wererecordedinCraco. In April 1971, Subsequently, duringthefall of1970,somesmall piles, deeplyfoundedintheclays. on linesofthick(800mm)reinforcedcontiguous and 4mwidereinforcedconcreteplatform,founded construction ofanew wall, consistingofa60mlong the totaldemolitionofoldretainingwall andthe stabilizing measureswerefi This Orderwas madepartialonlyin1968,andnew was issuedforthetotalevacuation ofthevillage. period ofdamage,aGovernment Order (D.P.R.), caused theevacuation of153houses.Following this developed fromtheJanuary1965reactivation, which had tobeabandoned.Even moreseriousdamage many cases,thedamagewas soheavy thatthehouses due totheactivation ofthetwo laterallandslides.In road suffered subsidenceandwereseverely damaged became almostunusable.Many housesuphillfromthe 2 mandahorizontaltranslationof1m,sothattheroad the 103StateRoadsuffered avertical displacementof village critical.InDecember1963,thewall protecting 1995 andJanuary1965,makingthesituationof landslide, occurredinDecember1963andJanuary Further acutereactivation anddevelopment ofthe of thelandslide,upliftexceeded 20m. some cracksinhousesuphillfromthewall. At thetoe and extensive displacementofthewall, andproducing causing completedestructionofthefootballpitch, followed byatotalreactivation ofthelandslide, fi station atPisticci;therainfall exceeded 400mmin measurements taken atthenearbymonitoring exceptionally heavy rainfall, asindicatedby In November 1959,theareaofCracoexperienced fl collapsed bridge. Gweneral view ofthetown fromBruscataRiver Stop 1: The visititineraryofCracowillinclude: Visit itinerary ve consecutive days. This exceptional rainfall was atten thegroundsurface. nne. hs involved These nanced. 24-05-2004, 15:23:43 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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Stop 2: Amato, 2000) and the SW-NE tectonic shortening Close view of the landslide crown. of the Apennine chain, connected with active compression against the stable Apulian Foreland, gave The Unstable Centre of Ferrandina rise to NW-SE trending “undulations”, which hosted F. Bozzano, A. Prestininzi, G. Scarascia Mugnozza the valleys of the main rivers. The interaction between glacio-eustatic sea level changes and regional uplift The geological-geomorphological caused the formation of eight different terraces in the context peri-Ionian coastal belt (Figure 3.5). The southernmost section of the Padano-Adriatic The main river valleys (Bradano, Basento, Cavone Foretrough, known as the Bradanica Trough (Fossa Agri, and Sinni rivers) generally show fl at-shaped Bradanica) Foreland is a structural depression, valley fl oors, and are divided by fl at-topped and placed between the Apennine and (from the plateau-like ridges. Gentle valley slopes are downcut present location of Bari, to the North, and the Gulf in a clayey bedrock (Blue Clays - Argille Azzurre, of Taranto, to the South). It is fi lled with a ca. 3000 made up of clayey strata, interbedded with silty m thick sandy-pelitic sequence, whose uppermost and sandy levels, whose frequency and thickness part belongs to the Bradanica Cycle (Lower - Middle increase upwards. The upper section of the hillslopes Pleistocene). The most recent deposits are made of are overlain by the above-mentioned coarse grain sands and conglomerates (Figure 3.5) (Valentini, deposits, whose overall thickness ranges between few 1979, 1995; Genevois et al., 1984; Bozzano and meters and, locally, 90 m. Scarascia Mugnozza, 1994). Most urban settlements of the area were founded on The rapid uplift which has involved the area since the such fl at-topped hills and have their borders generally Middle Pleistocene (Cosentino and Gliozzi, 1988; coinciding with the plateau edges. Along each Volume n° 1 - from PR01 to B15 n° 1 - from Volume

Figure 3.5 - Geomorphologic sketch of the Ferrandina area.

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi the degree ofretrogressionthecliff edges. areas intermsofbothreturnperiodlandslidesand great importanceasregards hazardconditionsofurban movement representsanacmeevent whichassumes In suchamorphodynamicscenario,eachslope range between0.2and3m/century(Valentini, 1995). Bozzano et al. as ontheelevation ofthesummitsurfaces (Bozzano lithology andageoftheuppermostdeposits,aswell The degree ofretreatthefl upper partsoftheclayey interfl terraced marinedepositswidelyoutcrop,covering the marked badlandtopography. ClosetotheIoniansea, ellipse shapedrelic.Here,theBlueClaysslopesshow respectively representedbyanarrow ridgeandbyan around MiglionicoandPisticci,thetopsurfaces are the presentcoastalplain(Figure3.5). As anexample, surfaces signifi interfl after aperiodofheavy rainfall whichcausedasudden involved thelocalityofCastelluccioinJanuary1960, erosion andlandslides,themostimportantofwhich escarpment. The town hillislargely affected byslope outcrop allaroundthehillslopesbelow thetoplayer conglomerates overlaying theBlueClays which River. The bedrockconsistsof90mthicksandy- a fl The town ofFerrandinaislocatedat492ma.s.l.over landslide atFerrandina The Castelluccio landslides remobilizedbythelandslide. Figure 3.6-SectionalongtheCastelluccioslope,showing theoccurrenceofancient at-topped hillontherightwatershed ofthe Basento , 1989;BozzanoandScarasciaMugnozza,1994; uvial ridge,the preservation oftheoriginaltop et al. cantly increasesfromtheinnerareasto , 1996).Estimatedratesofthisprocess at hilltopsdependsonthe uvial ridges. (more than1400m increase ofriver discharge intothesurroundingarea This situationisalsopresentinmostslopesofthe eluvial-colluvial materials. a sequenceofancientlandslideheaps,buried under A sectionofthelandslideslope(Figure.3.6)shows retrogressive retreatalongasingleslidingsurface. previous landslidebodiesthoughamechanismof new generatedmovements which,however, reactivate surface. The slopeevolution appearstoberelated rotational slip(Hutchinson,1988)alongasingle The slopemovements canbeclassifi thus contributing tothetriggeringofmovement. signifi hydraulic boundaryconditionsinsidetheslope,and coarse grainsubhorizontalstrata,determinedthe between theclayey substratumandtheoverlying 1984). Moreover, thedifference inpermeability cracks paralleltothecliff trend(Cherubinietal., this deformationcontrastweresubvertical tension by strain-softeningbehavior. Obvious effects of substratum (overconsolidated clay),characterized rigid cap(sandy-conglomerates)andthesofter to thecontrastindeformationbetween The slopefailure mechanismwas mainlyrelated (Bozzano, 1992). estimated depthoftheslidingsurface was 100m level, andtheunderlyingblueclays;maximum movement involved thetopsandy-conglomeratic fl long, excluding thedistalportion,whichmoved asa The displacedmasswas ca.400mwideand950 ow over ca.1000mdown totheBasentoRiver. The cantly infl uenced theporepressuredistribution, 3 /sec intheBasentoRiver). ed asamultiple 24-05-2004, 15:23:48 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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surrounding area, where the Blue Clays are overlain the world owing to its largely documented eruptive by a stiff sandy-conglomerate cap. history, and because of its spectacular almost continuous activity which lasted for around three Visit itinerary centuries until 1944; and, of course, because of Pompei, one of the best preserved archaeological sites Stop 1: in the world. Close view of the Castelluccio landslide crown, and During the Quaternary, the Tyrrhenian margin of general view of the landslide area. central and southern Italy was strongly characterized by the development of K- rich volcanoes. This activity Stop 2: started around 2 My BP, and lasted until the present Observation of the mobilized slope materials in a day, with the historical eruptions of Vesuvius, the section on the left side of the Casteluccio landslide. Flegrean Fields, and the Island of Ischia (Santacroce, 1987, and references herein). Field itinerary Vesuvius can be considered quite a young volcano, since it is not older than 30-35,000 yr BP. In the past, its general shape was very different from the present one, that is, a regular cone, surrounded by an older apparatus, called Mount Somma (Figure 4.1). Indeed, the slopes of Mount Somma are the relics of an older volcano, whose activity ended with a summit caldera collapse. Inside this caldera, the more recent cone of Vesuvius has built up. The activity of Vesuvius alternates long periods of quiescence with Plinian eruptions, and small-size, effusive and slightly explosive events (Bonasia et al., 1984). Since the XV century, Vesuvius was persistently active until the last effusion in 1944. This period of activity was characterized by several cycles, each one of which began after a time lap of no more than 7 years (Bonasia et al., 1984). Generally Volume n° 1 - from PR01 to B15 n° 1 - from Volume DAY 3 From Pompei to San Benedetto del Tronto Figure 4.1 - Schematic geological map of Mt. Somma – Vesuvius area. Legend: 11a Potassic vulcanics: Pompei and the 79 A.D. undersaturated (Quaternary); 11b: volcanites with Eruption of Vesuvius hydromagmatic facies (Quaternary); 35-36: Shallow- P. Molin water limestones and subordinate dolomites (Eocene- Vesuvius is probably the most famous volcano in Upper Triassic). (after Bigi et al., 1992).

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi magmatic chambertopcollapsed,and After thepyroclastic fl 2001). Miseno (GiacomelliandScandone, in theatmosphereandreachedCapo whereas adensecloudofashspread the towns surroundingthe volcano, whose depositscompletelyburied pyroclastic fl morning of August the25th,several Stabia (Figure.4.4). At theendof in theareaofErcolano,Pompeiand the volcano, destroying everything quickly fl that exited fromthecraterandvery very hotmixtureofpumiceandash, of pyroclastic fl eruptive column,andthegeneration the activity began again,withthecollapseof people wentbacktheirhomes,but inthemorning the apparentpauseineruption,atnightseveral and byathickpumicefall deposition.Owingto and was characterizedbyfrequentearthquakes, This phaseoftheeruptioncontinueduntil8a.m., Vesuviano web site). (from theOsservatorio eruption of79 A.D. Vesuvius before the Pompei, showing painting found in Figure 4.3-Fresco in thebackground. of Pompei with Vesuvius Figure 4.2-Excavation owed down thesidesof ows continuedtoform, ows, adenseand of 15-20km. from thevolcano toaheight ash, gasses,andlithicsrose eruptive columnofpumices, the upwellingmagma. An of thegroundwater with following theinteracting through several explosions opening oftheconduct around 1p.m.,withthe hours. The eruptionstarted pumice andashwithin30 more orless4km eight centuries,erupting after aquiescenceofaround Vesuvius began itsactivity On August 24,79 A.D., fountains andanexplosive and endedwithlava and Strombolianactivity, started withgentleeffusive speaking, every cycle (Santacroce, 1987). eruptive columnof5-15km and bytheformationofan by ahighereffusion rate, eruption, characterized os the ows, 3 of pumice fall, pumicefl into aneruptive sequencethatprogressesthrough excavation. Here,thestratigraphycanbegeneralised is preserved intheOplontis(“Poppea’s villa”) The mostcompleterecordoftheeruptive events surrounding Vesuvius (Santacroce,1987). sourcing areas,inducedsevere damageinthezones of thesurface drainage,asfar as5-7kmfromthe These mudstreams,fl –fl steep slopesofthevolcano, generating“lahars” Heavy rainssoaked andmobilisedtephraonthe dangerous effects (GiacomelliandScandone,2001). of hugeamountsloosematerialsresultedinvery For awhileaftertheendoferuption,deposition as a“plinian”eruption. phenomenon, soviolentanddestructive, isreferredto by boattohelpsomefriends. That iswhythiskindof death ofhisuncle,Pliny theElder, wholeftMiseno volcanological studies. Intheletters,herecounted to Tacitus, thatrepresentanimportantreportfor described byPliny the Younger intwo famous letters must have taken justafew days. The eruptionwas explosions (Santacroce,1987). The overall process warmed upbythemagma,inducingasuccessionof the groundwater infi Pompei eruptionsuggeststoushow dangerous beginning oftheeruption. Therefore, the79 A.D. quickly, andcanalsooccur several hoursafterthe phase ofanexplosive eruptioncanbeover very just afew days,andreportthatthemostdangerous and historicalsourcestellusofatragedythatlasted After two thousandsofyears,geology, archaeology, and muddeposits(Santacroce,1987). ows ofdensemudmixed withcoarsematerials. Figure 4.4-CastsofsomevictimsinPompei (from theOsservatorio Vesuviano web site). ltrated thehotrockspreviously owing alongthemainchannels ow, ashfl ow, pyroclastic surge 24-05-2004, 15:23:53 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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Vesuvius still is, especially taking into consideration This destructive event is just one of the last events the surrounding belt of dense urban settlements. that characteristically involve the pyroclastic material present along the limestone Campanian Apennines The Sarno catastrophe slopes (Figures. 4.6-4.7). F. M. Guadagno. The volcanoclastic airfall deposits were placed, in On 5-6 May 1998, after prolonged rainfall, a large varying thicknesses, during periods of volcanic activity number of landslides occurred, at different times, in of the Somma-Vesuvius and Phlegraean Fields. Their the area of the towns of Sarno, , Siano, and cyclic deposition, separated by periods of weathering, Bracigliano, situated at or near the base of the slope of creates a complex sequence of soils. The individual Pizzo d’Alvano, and caused the death of 161 people layers have contrasting characteristics in terms of (Figure. 4.5). lithology, grain size, and thickness. This layered

Figure 4.5 - Photo of debris avalanche paths reaching the town limits of Sarno. Volume n° 1 - from PR01 to B15 n° 1 - from Volume

Figure 4.6 - Pyroclastic materials overlying Figure 4.7 - A block diagram showing the peculiar the limestone slopes in the Sarno area. geomorphologic setting in the Campanian Apennines (after Celico et al., 1986, modifi ed)

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Volume n° 1 - from PR01 to B15 B08 - B08 started fromaroadcut. Figure 4.9- A fl Leaders: F. Dramis,A.Prestininzi m event, several millionsof 1998 Sarno-Quindici of theslopes.During and hydrologicalbehavior it controlsthemechanical landslide phenomena,as to thedevelopment of structure isfundamental fl avalanches anddebris and wereclassifi displaced inthelandslides, the Pizzod’Alvano slopes, place onthesteepestpartsof The initialmovements took developed intodebrisfl became channelized,and debris avalanches. Many the slope,tobecomefl material andwater from expanded, byincorporating initial debrisslides,thatthen They startedoff asshallow al. ows, following Hungr 3 (2001)(Figure.4.8). ofslopematerialswere ow movement ed asdebris ows. uid et Figure 4.8-Pattern ofthe1998fl confi fl steep slopes. Vegetation damageindicatesthat the the pathwas 10-20mwideatthebase,borderedby slopes, atanglesof20to35°.Inatypicalgullysector, become channelizedinthegulliedterrainofmid- as 380m(Revellino individual debrisavalanche scarsreachedasmuch debris avalanche scars. The maximumwidthsofthe paths exhibit atriangularshapeinplan,typicalof increase inwidth,theupperreachesofmany ofthe and baseofthepaths. As aresultoftheprogressive and colluvialsoils(0.5-2mthick),fromthesides considerable velocity, erodingpyroclastic horizons slopes. Shortlyafterinitiation,thelandslidesacquired mobility toreachbuilt-up areasnearthebaseof more thantwentylongdebrisfl failures (Guadagno located withinthepyroclastic mantle. About 178initial distance above orbelow thecutslopeofatrackway, About 60%oftheinitialslidesoccurredashort 4.9) (Guadagno,2000). and artifi have beencontrolledbythepresenceofnaturalscarps of gullies. The locations oftheinstabilitiesappearto on surfaces inclinedat40°-50°,oftentheheads ow depthwas typicallyofthe orderof5-6minthese ned reaches. cial trackways cuttingtheslopes(Figure. ows along thePizzod’Alvanoridges et al. et al. , 2003a),combinedtoform , 2003).Mostofthefl ows, withsuffi 24-05-2004, 15:24:00 cient ows LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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Several bends in the fl ow paths give an estimated Field itinerary maximum fl ow velocity of more than 15 m/s. On leaving the gullies, the fl ows issued onto relatively gently-sloping fans or aprons, consisting of pyroclastic material. The origin of these geomorphologic features is uncertain, but the presence of fresh and relatively well-sorted pumice layers within them suggests that they were at least partly built simultaneously with the deposition of the tephra. Their shape is smooth and their typical slope angle is 10° to 15°. It is possible that colluvium, i.e. old debris fl ow fan and apron deposits, exists within these features, predating the deposition of the present pyroclastic mantle. The present slope morphology may thus mimic the paleomorphology of the older deposits. DAY 4 From San Benedetto del Tronto to Orvieto Flow depths were typically of the order of 4-5 m in this zone. Organic debris was discarded at the upstream margin of the urbanized areas. The velocities decayed A large-scale landslide affecting fairly rapidly, following the onset of deposition. The an ancient village in Central Italy: maximum thickness of the deposits was of 3.5 - 4 m in the Montelparo landslide M.-G. Angeli, F. Pontoni, F. Dramis the central part of the fl ow paths. Contemporary video clips recorded in the distal parts of the deposition The medieval village of Montelparo is located in a areas show fl ow fronts moving through narrow streets hilly area of the Marche Region, to the east of the at several meters per second. Apennine chain. It is affected by a large translational The material arriving in the deposition area was landslide that has developed from 580 m a.s.l. to 340 dense, but extremely fl uid. In several instances, m a.s.l., with a length varying between 700 and 1100 rooms were fi lled with mud to a depth of several m and an average width of 600 m (Figure 5.1). meters through door and window openings. Some of the fl ows reached established drainage pathways and incorporated additional surface water, eventually transforming into debris fl oods (hyperconcentrated streamfl ow) in the distal reaches of the deposition areas (Pierson and Costa, 1987). Visit itinerary The visit to the Sarno area will include the following itinerary: Figure 5.1 - Frontal view of the landslide area Stop 1: The landslide body is part of a monocline, dipping Short talk on Sarno landslides; environment and 10°-12° NE, made of well-stratifi ed sandstones, occurrence in front of the mobilized slope; overlying a deep-seated clayey bedrock. A system of direct faults and the erosion operated by the Fosso di Stop 2: S. Andrea stream, fl owing at the toe of the slope have Impact area and observation of the damage on favored the detachment of the sandstone slab (up to buildings and structures; 65-70 m thick) sliding on a clayey sloping slip surface, PR01 to B15 n° 1 - from Volume and the formation of a well-marked depression, fi lled Walk along a channel and observation of the with debris material on top of the hill (Figure 5.2). material involved in landsliding and the transit area The lowermost part of the sliding slab, much thinner morphology. than the upper one, is characterized by a progressive disruption into blocks, divided by cracks (up to 3-5 m deep and 2-3 m wide). In other words, the Montelparo hill is split into

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi graben area(onthesubvertical face ofthemoving triangular water pressurediagramoperatesinsidethe similar totheonesoccurringinrockslides,wherea In theshortterm,criticalhydraulicconditionsare by about3m,atanaverage rateof 8cm/year. established that,in35years,thetrenchhadwidened derived fromaerialphotographs,dated1970,itwas a cadastralmapdatingbackto1935,andnew map of upto2-3cm(Angeli carried outin1980,showed horizontaldisplacements months. Inaddition,precisiontopographicsurveys, months, toca.2.5cm/monthfortheremaining6 speed varied from0.3cm/monthforthefi displacements of20-25cmtookplace. The average March 1979establishedthatalongthetrench,vertical Leveling surveys carriedoutfromMay1977to and alongitsmargins (Figures5.3-5.4). occurred onlywithinthisslowly expanding depression literature (Pastori, 1781).Majordamagestobuildings struck theareain1703,isreportedhistorical coincidence withthehighintensityearthquake which An importantreactivation ofthemovement in area have beendocumentedsincetheXVIIcentury. Damages inducedbythelandslideinbuilt-up with thefi the sub-vertical planecutintothebedrockincontact the upperlimitofdepressionisexposed, showing Hutchinson (1969).Onthenorthernfl basis oftheclassifi known ingeotechnicalliteratureasagraben,onthe settlement occurs(Angeli,1981). This lastareais In theintermediatearea,aprocessofcontinuous buildings donot show any majortiltingfracturing). the downhill partisslowly moving asawhole(the two parts:theuphillpartthatisstable,whereas indicates themoving partofthevillage) Figure 5.2-Grabenstructure(thehorizontalarrow lling debris. cation donebySkempton and et al, 1996).Bycomparing ank ofthehill, rt 16 rst slip surface (Figure5.5). drainage, usefultoincreasetheshearstrengthon Angeli The maincontrolworks (AngeliandPontoni,2000; permanently low, wellbelow thecriticalvalues. the importanceofmantainingwater levels body andatitsbase)increaseexponentially. Hence makes thewater thrusts(ontherearoflandslide the mechanisminvoked, any increaseinwater level piezometric peakswerealsorecorded. According to event occurringinDecember1999,whensignifi movement incoincidencewitharainfall critical mechanism was provided bytheaccelerationof clayey slipsurface. An indirectconfi mass), andarectangularoneactsonthesloping the built-up hilltopprofi General view ofthetown withparticularemphasison Stop 1: Montelparo: The following observation itinerarywillbeheldin Visit itinerary al clayey-sandy-conglomeratic terrains(Cantalamessa vergence, madeupoflower-Middle Pleistocene slopes ofcompressive structureswithan Adriatic These landformsarefrequentonthenortheastern through anarrow coastbelt. cliffs, presentlyinactive andseparatedfromthesea lowering seawards, have been foundinwave-cut coastline, locallyborderedbyfracturesandsteps Along the Adriatic coast,trenchesparallelwiththe F. Dramis,G.Pambianchi, B.Gentili Landslide The Ancona materials. Close upview ofasectionshowing thetrenchfi Stop 3: movement, Walk inthetown toseetheeffects ofthedeepseated Close upview ofthewall crossingthetrench; Stop 2: (tectonic-gravitational spreading),inducedbyactive mainly todeep-seatedgravitational deformations The originoftheabove landformsistobereferred Riguzzi recently affected thearea(Gasparini by thehypocentralmechanismsofearthquakes which , 1987). These structuresarestillactive, astestifi et al et al ., 2002)belongtothecategory ofthedeep , 1989). le interruptedbythetrench; rmation ofthis et al 24-05-2004, 15:24:07 , 1985; lling cant ed et LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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compressional tectonics (Dramis and Sorriso-Valvo, 1994). Within this framework, large scale rotational- translational landslides and listric faults, lowering toward the Adriatic Sea, are produced (Coltorti et al, 1984). One of the most representative examples of the above-mentioned phenomena is the deep-seated gravitational slope deformation which involved the north-facing slope of Montagnolo Hill, in the western Figure 5.3 - Rupture in the wall which crosses the Montelparo trench. The buildings on the left side are outskirts of Ancona. Here, on the evening of the 13th located in the stable portion of the hill; the rupture December 1982, after a period of heavy rain, a huge indicates the upper margin of the trench. landslide took place (Figures 5.6-5.7-5.8), over an area of more than 3.4 km2, from about 170 m a.s.l. to the Adriatic coast (Crescenti et al, 1983; Coltorti et al, 1984; Crescenti, 1986). The phase of rapid deformation, which started without warning, lasted only a few hours, and was followed by a longer period of settling. More than 280 buildings were injured beyond repair, and many of them collapsed completely (Figure. 5.9). The Adriatic railway, along the coastline, was damaged over a distance of about 1.7 km (Figure. 5.10). Luckily, there were no victims. The slope hit by the landslide has had a long history Figure 5.4 - The progressive enlargement of the of gravitational movements (Bracci, 1773; Segrè, Montelparo trench from 1920) (Figure 5.11). In 1858, it was the site of a 1812 to 1970. landslide even larger than the recent one (De Bosis, depressions, and reverse slopes (Figure 5.12). 1859). More shallow mass movements, still large in Moreover aerial photo analysis showed that several an absolute sense, have occurred in the landslide area. deep open fractures and fl exural scarps were produced Of these, the Barducci mudfl ow is well known for its after 1956 and before 1979, in the area of the main continuous activity, and the damage it has wreaked on detachment zone of the 1982 landslide. It is most the coastal road and railway (Segrè, 1920). likely that similar surface displacement was related to From a stratigraphic point of view, the lithotypes the 1972-74 earthquake sequence (Cotecchia, 1997). outcropping on the landslide-affected slope are the The rainfall period that occurred in Ancona 10 following: days before the catastrophic 1982 landslide was 1) Lower to Middle Pliocene deposits (grey-blue characterized by an amount of precipitation not marly clays, 20-40 cm thick, alternated with grey or grey-black compact sands, up to 60 cm thick); 2) Pleistocene deposits, consisting of fi ve transgressive-regressive cycles of pelitic-arenaceous units, with a total thickness of about 20 m. The area has been uplifted starting at the end of Early Pleistocene. Coquinic panchina and sands at the top of the clayey beds (Montagnolo Hill, 250 m a.s.l.) are probably related to the early stages of the uplift. Figure 5.5 - Diagrammatic cross-section with the main PR01 to B15 n° 1 - from Volume From a geomorphological point of view, the study control works planned. area displays an overall smoothed morphology, with moderate relief and gentle slopes. The observation particularly relevant from the hydrologic point of of aerial photographs, taken before the event of view. Therefore, a fundamental role for the generation December 1982, shows a characteristic landslide of the 1982 landslide was played by the co-seismic morphology, with trenches, scarps, steps, undrained opening of the numerous fractures.

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi fractures inthebackground. Figure 5.8- View oftheuppertrench, withthemainscarpinforeground, and“antithetic”scarplets escarpments andtrenches. landslide, showing themain model ofthe Ancona Figure 5.7-Digitalelevation landslide. the December1982 Ancona Figure 5.6- Aerial viewof 24-05-2004, 15:24:11 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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Figure 5. 9 - Heavily- damaged buildings in the 1982 landslide affected area.

Visit itinerary The visit itinerary to the Ancona landslides will include:

Stop 1: General view of the landslide slope from the edge of the main scarp; Stop 2: A walk down the main landslide scarp to the upper trench. Stop 3: Close up view of tilted and crushed water wells in the trench. Stop 4: A walk from the upper trench to the lower trench; view of landslide secondary scarps and damaged buildings. Stop 5: Close up view of a 16th century post-house, showing Figure 5.10 - Damage to the Adriatic railway at the the cumulative effects of past landslide movements. landslide toe. Field itinerary slow but inexorable degradation of the historic town, by progressively reducing its size. DAY 5 The aim of this excursion day is that of illustrating From Orvieto to Florence the geological-geomorphologic features of Orvieto’s Cliff, explaining the causes of the town’s instability, Orvieto: a Case of an Unstable Town and describing the works (the majority of which C. Cencetti, P. Conversini, P. Tacconi were realized recently) aimed at the conservation and consolidation of the cliff and the historic center Introduction of town. Orvieto, one of the major historic-artistic towns of Central Italy, lies in the province of Terni, about Regional geologic setting 100 km north of Rome, at the boundary between the Orvieto’s Cliff (Figure. 6.1) is an erosional relict of Regions of Umbria and Latium. the edge of the Alfi na Tuffaceous Plateau, a product PR01 to B15 n° 1 - from Volume The town was built by the Etruscans in the IX-VIII of the volcanic activity, related to the Tyrrhenian century B.C., over a small tuffaceous cliff (about rifting, which affected central-western Italy during 1.3 km2 in area). The town suffers from instability the Middle Pleistocene. Its eruptive center (Vulsini conditions, due to the particular geological and Volcanic Complex) corresponded to the present-day geomorphological features that are the main cause of Bolsena Lake (Alvarez, 1975; Varekamp, 1980; the landslides affecting the cliff’s perimeter. Faraone and Stoppa, 1988; Lavecchia, 1988). The mass movements have produced, over time, a The stratigraphic series of the Orvieto area (Figure.

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi bedrock, startingfromtheupperlimitofcliff. Gullies, upto10-15mdeep,locallyincisetheclayey bedrock. distributed alongtheslopesoverlying theclayey the baseofwholeOrvietoCliff, and arevariously produced byphysicalweatheringofthetuff, surround River Paglia alluvialplain.Clasticsediments(talus), clays ofPlioceneage,gentlysloping(15°-18°)tothe The Cliff liesonthetopofahillmodeledover marine et al. width, andbetween4070minthickness(Basilici measurements are1500minlength,about700 walls, higheralongthesouth-westernside.Its It liessub-horizontally, withvertical orsub-vertical in shape,withitsmajoraxisorientatedENE-WSW. The tuffaceous cliff sustainingOrvietoiselliptical constituting theCliff properlynamed( Series in fl Conversini 6.2) isupward characterized(Pialli The instabilityofOrvietohasbeenknown since the The landslidesofOrvieto Montagnolo slope. Figure 5.11- A 16 uvial-lacustrine facies ofthinthickness( , 2000). ) and,atthetop,bytuffaceous plate, et al ., 1995)bymarineclays,sediments th centurypost-house,showing thecumulative effects ofrecurrentlandslidemovements onthe the “Rupe” et al Albornoz ., 1978; ). (Manfredini phase ofthepyroclastic high-temperaturefl the cliff perimeter, aretheconsequenceofcooling cracks, whichareclearlyvisiblealongthewholeof the distribution ofcracksinthetuffaceous rock. The The rupturemechanismsofthecliff arerelated to (Figure 6.3). the cliff, andbasalrupturesofblocks ofvarious size rock falls ortopplesinthemiddle-upperportionof to lowerings ofmarginal slicesalongtheupperedge, tuffaceous plate,therupturemechanismsarereferable clays themselves. Instead,alongtheperimeterof water table,whosebaselevel isrepresentedbythe clays. This situation isrelatedtothepresenceofa the clasticsediments,orofupperportion of theselandslidesistheprocesssaturation lithotypes, separatelyortogether. The main cause and translationalslidesinvolve thetwo different covered byclasticdetritialsediments, rotational Along thehillslopes,wherebasalclaysare of thetuffaceous rock,andofitsclayey substratum. It iscloselyrelatedtothelithologicalcharacteristics Lotti, 1908;MartiniandMargottini, 2000). XII century(Vinassa deRegny, 1904; Verri, 1905; et al. , 1980;CestelliGuidi et al. 24-05-2004, 15:24:18 , 1983; ow ow LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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Figure 5.12 - Geomorphological sketch (a) of the Ancona landslide slope (after Dramis and Blumetti, in press); b. Landslide sections; c. Tectonic pattern.

Lembo Fazio et al., 1984; Regione Umbria, 1990). slopes. Also, human activity has played an important role in The main works, completed at present, are all the instability of Orvieto, owing to the exploitation aimed at mitigating the hill’s natural morphological of the tuff of the cliff. With respect to this problem, evolution, and eliminating the negative effects of the concessions by local Authorities for quarrying human activity. They may be summarized as follow “pozzolana” (a typical tuff of Orvieto) inside the Cliff (Lunardi and Fornaro, 1980; Pane and Martini, 1997 are very important. – Figure 6.4): - stabilization of the landslides along the Remedial measures slopes (by means of deep drainage wells

The Royal Decree of March 7, 1937 included Orvieto and trenches, retaining structures, and slope PR01 to B15 n° 1 - from Volume in the list of towns “to be preserved at a total expense reshaping); of the State”. Nevertheless, until the mid 1970s, - hydraulic improvement of the gullies (by remedial work was sporadic and aimed at remedying means of reshaping, partial coating, and urgent and risky local situations (Pane and Martini, check dams); 1997). In 1977, the Umbria Region established a - hydraulic and landscape reclamation, to global program aimed at a defi nitive consolidation control the erosive action of the waters of Orvieto, through a monitoring of the Cliff and its (by means of reafforestation, springs

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Volume n° 1 - from PR01 to B15 B08 - B08 Pliocene bedrock); 6:Paglia River anditsmaintributaries 4. gravels, sands,andclays(marine clasticsediments,Lower Pleistocene–Pliocene);5.marlsandsandstones(pre- sediments, alsoterraced(Holocene-UpperPleistocene);3.volcanic rocks ofthe Alfi Figure 6.1-Geologicalsketch oftheOrvietoarea.Legend:1.talus(Holocene);2.recentandpresentalluvial Leaders: F. Dramis,A.Prestininzi Cliff (afterConversini etal.,1995,modifi Figure 6.2-Schematic geologicalsectionoftheOrvieto ed). na Plateau(MiddlePleistocene); 24-05-2004, 15:24:22 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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Figure 6.3 - Typical mechanisms of instability: A. rotational slides at the cliff’s toe; B. lowering of marginal slices; C. topples and rollings; D. falls and basal ruptures (after Regione Umbria, 1990).

interception, waterproof channeling etc.); - strengthening of the tuffaceous cliff (by means of active and passive anchors, nails, and drain pipes); - consolidation of the underground cavities; - complete substitution of the old aqueduct and sewage system; Figure 6.4 - Scheme of stabilization works along the cliff (from - strengthening and restoration of the historic walls founded close to the cliff brow. At the same time, the Umbria Region installed a network of instruments for hydrological, geotechnical and topographic measurements, within a “Permanent Observatory for the Control and Maintenance of the Orvieto Cliff” (Pane and Martini, 1997). Visit itinerary The visit itinerary provides seven observation stops, as in the attached map (Figure 6.5):

Stop 1: PR01 to B15 n° 1 - from Volume at the parking lot in front of Etruscan Necropolis. This viewpoint lets us examine the characteristics of the cliff on its NE slope. The morphological contrast, due to selective erosion processes, between the tuffaceous plate (with tabular morphology, such as it can

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi Stop 3: Visit totheEtruscanNecropolis. Stop 2: deep gullies),canbeobserved. be comparedtoa progress, areclearlyvisibletoo. Rocca Ripesena’s Turning toface toward WNW, Bardano’s the aimofassigningmarginal landstoagriculture. badlands areaswerereclaimedbyhumaneffort, with clays outcroppingontheleftbankofriver. Many badland morphologyaffecting the Pliocenemarine the toeofOrvietoHill;itispossibletoobserve the of the Valley ofthePaglia River, whichfl Panoramic view fromCahenPlacetowards north,

mesa butte, ), andthehillslopes(cutby anderosionalprocessesin Figure 6.5-Theobservationstopsalongthefi os at ows mesa , neighborhood ofthe Well thereexists anancient regained by PopeClemente VII; intheimmediate Visit toCava’s Well, probablyof Etruscanorigin, Stop 7: excavated Visit totwo wide caves locatedwithintheCliff, Stop 6: Gothic artinUmbria. The Cathedral,themostimportantexpression of Stop 5: by meansofpackanimals. the Orvietoinhabitantsdraw water, inancienttimes, was plannedby Antonio daSangalloilGiovane, tolet Visit totheFortress andSt.Patrizio’s Well. The Well Stop 4: ≠ sinceEtruscanage. eld itinerary. 24-05-2004, 15:24:27 LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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pottery, active between the end of the XIV century di Agraria, Università di Perugia 35, 207-222. and the middle of the XVI century, regained at present Angeli, M.-G., Bisci, C., Burattini, F., Dramis, F., after a diffi cult excavation and open to the public. Leoperdi, S., Pontoni, F. and Pontoni, F. (1996). Evolution and triggering factors of large- Stop 8: scale landslides affecting built-up areas in the Walk along the toe of the cliff, where it is possible to Marche Region (Central Italy). Quaderni di examine the strengthening works of the cliff carried Geologia Applicata, 3 (1), 131-140. out so far, and the installed monitoring instruments. The vertical cracks in the volcanic rock are also Angeli, M.-G., Leonori, L., Leoperdi, S. and Pontoni, visible as well as the reinforcement measures aimed F. (2002). From analysis to remedial works: the at avoiding the disastrous fall of tuffaceous blocks. case of Montelparo Landslide (Central Italy). In the past, reinforcement and supporting works were In “Natural Hazards on Built-Up Areas”. CERG carried out using fl asks to separate the cracked blocks Intensive Course, Camerino (Italy), September and sustaining, by means of breast walls, the others, 25th-30th 2000, 117-121. thus preserving a precarious equilibrium. Afterwards, Angeli, M.-G.and Pontoni, F. (2000). The innovative starting in the 1970s, nails and anchors, placed at use of large diameter microtunnelling technique various heights, were used, whose heads, at the end of for the deep drainage of a great landslide in the interventions, were hidden by means of tuffaceous an inhabited area: the case of Assisi (Italy). mortars. These works enabled the cliff to reacquire its 8th International Symposium on Landslides, natural look. Cardiff, June 26-30, 2000, vol. 1, 1665-1672. References Arca, S. and Marchioni, A. (1983). I movimenti Acocella, V. (1951). Storia di Calitri. Ed. Federico & verticali del suolo nelle zone della Campania Ardia, Napoli. e della Basilicata interessate dal sisma del Agnesi, V., Carrara, A., Macaluso, T., Monteleone, 23.11.1980. S., Pipitone, G. and Sorriso-Valvo, M. (1982). Bollettino di Geodesia e Scienze Affi ni 2. Osservazioni preliminari sui fenomeni di Arias, A. (1970). A measure of earthquake intensity. instabilità dei versanti indotti dal sisma del 1980 In “Seismic design for nuclear power plants” nell’alta valle del Sele. Geologia Applicata e (R.J. Hansen Ed.), Cambridge, Mass., M.I. T. Idrogeologia, 17, 79-93. Press. Agnesi, V., Carrara, A., Macaluso, T., Monteleone, Baratta, M. (1901). I terremoti d’Italia. Ed. Fratelli S., Pipitone, G. and Sorriso-Va1vo, M. Bocca, Torino, 950 pp. (1983). Elementi tipologici e morfologici dei Bartolini, C., D’Agostino, N. and Dramis, F. (2003). fenomeni di instabilità dei versanti indotti da1 Topography, exhumation, and drainage network sisma del1980 (alta valle del Sele). Geologia evolution of the Apennines. Episodes ,23 (3), Applicata e Idrogeologia 18, 309-341. 212-217. Alfano, G.B. (1930). Un terremoto irpino del luglio Basilici, G., Brozzetti, F., Cencetti, C., Conversini, P., 1930. Osservatorio di Pompei. Stoppa, F. and Tacconi, P. (2000). Geological, Alvarez, W. (1975). The Pleistocene volcanoes North geomorphological and hydrogeological maps of Rome. In “Geology of Italy”, Earth Sciences of the Todi Hill and the Orvieto Cliff (Umbria, st Society, Arab Republic, Tripoli, 355-377. Central Italy). Abstracts Volume (Cd-rom), 31 Amato, A. (2000). Estimating Pleistocene tectonic International Geological Congress, Rio de uplift rates in the Southeastern Apennines Janeiro, Brazil, August 6-17, 2000. PR01 to B15 n° 1 - from Volume (Italy) from erosional land surfaces and Bellino, S. and Maugeri, M. (1985). Confronto tra marine terraces. In “Geomorphology, Human valori di resistenza residua ottenuti con diversi Activity and Global Environmental Change” apparecchiature anulari di taglio. Rivista (O. Slaymaker, Ed.), pp. 67-87, John Wiley & Italiana di Geotecnica, 19 (2), 101-113. Sons, Chichester. Bertini, T., Cugusi, F., D’Elia, B. and Rossi-Doria, Angeli, M.-G. (1981). Sulle condizioni di stabilità M. (1984). Climatic conditions and slow dell‘abitato di Montelparo. Annali della Facoltà movements of colluvial covers in central Italy.

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi Bozzano, F., DePari, P. andScarasciaMugnozza,G. Bozzano F. (1992). Analisi deiprocessididinamica Bonaria, V., DelPezzo,E.,Pingue,F., Scandone, Bollettinari, O.andPanizza, M.(1981).Una“faglia Bisci, C.,Dramis,F., Cecili, A. andCipolloni, Bisci, C.,Dramis,F., Cecili, A. andCipolloni,C. Bisci, C.andDramis,F. (1993).Earthquake related Bigi, G.,Cosentino,D.,Parotto, M.,Sartori,R.and Bertini, T., Cugusi,F., D’Elia,B.andRossi-Doria, 7 “Landslides” (K.Senneset,Ed.),pp.159-164, hazard insomevillagesSouthernItaly. (1996). Historicaldatainevaluating landslide Sapienza” University, Roma. Fossa Bradanica. geologico-strutturale plio-quaternariadella dei versanti inrelazioneall’evoluzione (3), 395-406. Mt. Vesuvius,Italy, seismic activity andgrounddeformationsat R. andScarpa,(1985).Eruptive history, 135-139. Rendiconti dellaSocietàGeologia Italiana occasione deisismadel23-11-1980inIrpinia. di superfi geomorphometric analysis.Inpreparation. Italy atamediumscalebasedonhierarchic C. Zonationoflandslidesusceptibilityin Department, University ofStrasbourg and MaquaireO.,Eds.),pp.15-20, opinion tomodelling” results. distribution ofslopeinstability:preliminary defi (2002). A new approachtocomputeraided Science Forum ‘92 mass movements inItaly. Scientifi ca” and gravity map. Scandone, P. (1992).StructuralmodelofItaly Geotecnica stabilizzazione. nell’Abruzzo adriatico:caratteriecriteridi M. (1986).Lentimovimenti diversante Toronto, 1,367-376. IV InternationalSymposiumonLandslides th InternationalSymposiumonLandslides nition ofsomeparametersdescribingthe cie” pressoSanGregorio Magnoin In , Bologna,1,91-100. , 114(3),CNR,Roma. “Geomorphology: fromexpert XVI Convegno Nazionaledi , Sapporo,40-55. Doctoral thesis Quaderni de“LaRicerca Annales Geophysicae

(Delahaye D.,Levoy F. Hokkaido Earth Geography . , “La , 17- , 95, In 3 ,

Canuti, P., Garzonio,C..A.andRodolfi Canuti, P., Cascini,L.,Dramis, F., Pellegrino, A. Canuti, P. (1983). Ambienti geologiciinvestigati Cantalamessa, G.,Dramis,F., Pambianchi, G., Cantalamessa, G.,Centamore,E.,Cristallini,C., Cancelli, A., Pellegrini, M.and Tonnetti, G.(1984). Calcagnile, G.,DelPrete,M.,Monterisi,L.,Panza, Bracci, V. (1773).Relazioneallavisitafatta per Bozzano, F. andScarasciaMugnozza,G.(1994). Bozzano, F., Guadagno,F.M., Laureti,L.,Scarascia Natural Hazards Papers oftheInternational Workshop on occurrence, analysisandcontrol. and Picarelli,L.(1988).LandslidesinItaly: C.N.R., 227-234. “Conservazione delSuolo” Franosi’. nell’ambito delSubprogetto‘Fenomeni Geologia Italiana Molarae Bisaccia. sismica nell’areacompresatraS.Giorgio la (1981). Fenomenifranosiconnessiconl’attività Tonnetti,G. and Santoni, A.M. Romano, A., 26, 359-369. (Ascoli Piceno,Marche). sulla geologiadell’areadiPortoSanGiorgio Pontoni, F. andPotetti,M(1987).Nuovi dati Invernizzi, C.,Matteucci,R.,Piccini,M., Symposium onLandslides Adriatic Coast(CentralItaly). Geological featuresoflandslidesalongthe Teorica e Applicata geostructural frame. G. F. (1977).SeismicriskofBasilicatainits Ancona strada Flaminia. nei mesidiaprileemaggio1773auntratto ordine dellaCongregazione delR.Governo Romana, marini dell’arcoionicolucano. I fenomenidierosionenell’areadeiterrazzi Geologia Applicata eIdrogeologia, delle valli nordorientalidellaFossa Bradanica. depositi regressivi sull’evoluzione morfologica L’infl Mugnozza, G.and Valentini, G. (1989). 21 June1996, Trondheim. uenza degli assettilitostratigrafi . 30,769-778. Atti delConvegno Conclusivo-P.F. , Perugia,1988,165-184. Archivio diStato,SezioneIV, , 4(5),467-469. ,

Rendiconti dellaSocietà 9-10, 75-76,117-139. Bollettino diGeofi sica , Toronto, 2,7-12. Geologica Romana , Roma1982, IV International , G.(1979). 24,77-93. Geologica Selected 24-05-2004, 15:24:32 c dei ci , LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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Attività agricola e franosità: osservazioni Montalbano Ionico. Geologia Applicata e nell’area rappresentativa di Montespertoli Idrogeologia, 19, 121-145. (Toscana). Geologia Applicata e Idrogeologia Cinque, A., Lambiase, S. and Sgrosso, I. (1981). 14, III, 437-442. Su due faglie nell’alta valle del Sele legate Carmignani, L., Cello, G., Cerrina Ferroni, A., al terremoto del 23.11.1980. Rendiconti della Funiciello, R., Kalin, G., Mecchieri, M., Società Geologia Italiana, 4 (2), 127-129. Patacca, E., Pertusati, P., Plesi, G., Salvini, F., Cocco, E., De Magistris, M.A. and De Pippo, T. Scandone, P., Tortrici, L. and Turco, E. (1981). (1978). Studi sulle cause di arretramento della Analisi del campo di fratturazione superfi ciale costa lucano-ionica: 1- L’estrazione degli inerti indotto dal terremoto campano-lucano dei 23- lungo le aste fl uviali. Memorie della Società 11-1980. Rendiconti della Società Geologia Geologica Italiana 19, 421-429. Italiana, 4, 451-465. Colombetti, A., Pellegrini, M. and Zarotti, L. (1979). Carton, A., Dramis, F. and Sorriso-Valvo, M. (1987). The evolution of a slope with glacial and Earthquake landforms: observations after periglacial deposits in the higher northern recent Italian and Algerian seismic events. Apennines: the landslides of Febbio (Reggio Zeitschrift für Geomorphologie, N.F., Suppl. Emilia, Northern Italy). Polish-Italian Seminar Bd 63, 149-158. on Mass Movements, Warszawa 1979, 36-46. Catenacci, V. (1992). Il dissesto idrogeologico e Coltorti, M., Dramis, F., Gentili, B., Pambianchi, G., geoambientale in Italia dal dopoguerra al 1990. Crescenti, U. and Sorriso-Valvo, M. (1984). Memorie Descrittive della Carta Geologica The December 1982 Ancona landslide: a case d’Italia 47, Servizio Geologico Nazionale, of deep-seated gravitational slope deformation Roma, 301 pp.. evolving at unsteady rate. Zeitschrift für Celico, P. and Guadagno, F.M (1998). L’instabilità Geomorphologie, N.F,. 29 (3), 335-345. delle coltri piroclastiche delle dorsali Conti, A., Di Eusebio, L., Dramis, F. and Gentili, B. carbonatiche in Campania: attuali conoscenze. (1983). Evoluzione geomorfologica recente e Quaderni di Geologia Applicata 5 (1), 129- processi in atto nell‘alveo del Tenna (Marche 188. Meridionali). XXIII Congresso Geografi co Celico, P., Guadagno, F.M. and Vallario, A. (1986). Italiano, Catania, 2, III, 53-66. Proposta di un modello interpretativo per Conversini, P., Martini, E., Pane, V., Pialli, G., lo studio delle frane nei terreni piroclastici. Tacconi, P., Tortoioli, L. and Umbertini, L. Geologia Applicata e Idrogeologia 22, 73-193. (1995). La Rupe di Orvieto e il Colle di Todi: Cestelli Guidi, C., Croci, G. and Ventura, P. due casi di città fragili. I Convegno Gruppo (1983). The stability of the Orvieto Rock. Nazionale di Geologia Applicata, Giardini V International Congress Society of Rock Naxos, Messina, 1995, Geologia Applicata e Mechanics, C31-C38, Melbourne. Idrogeologia, 30 (1), 211-224. Cherubini, C., Guerricchio, A. and Melidoro, G. Cosentino, D. and Gliozzi, E. (1988). Considerazioni (1981). Un fenomeno di scivolamento profondo sulle velocità di sollevamento di depositi delle argille grigio-azzurre plio-calabriane nella eutirreniani dell’Italia meridionale e della valle del T. Sauro (Lucania) prodotto dal Sicilia. Memorie della Società Geologica terremoto del 23 novembre 1980. Rendiconti Italiana, 41, 653-665.

della Società Geologia Italiana, 4 (2), 155- Cotecchia, V. (1978). Systematic reconnaissance PR01 to B15 n° 1 - from Volume 159. mapping and registration of slope movements. Cherubini, C., Guadagno, F.M. and Valentini, G. I.A.E.G. Bulletin 17, 5-37. (1984). I fenomeni di erosione e di frana Cotecchia, V. (1981). Considerazioni sui problemi nei depositi argillosi della Fossa Bradanica. geomorfologici, idrogeologici e geotecnici Caratteristiche geotecniche e condizioni di evidenziatisi nel territorio colpito dal sisma stabilità delle colline argillose terrazzate di campano-lucano del 23 novembre 1980

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi D’Agostino, N.,Dramis,F., Funiciello,R.and Crescenti, U,Dramis,F, Prestininzi, A. and Cotecchia, V., Travaglini, G.andMelidoro,(1969). Crescenti, U.,Dramis,F., Gentili,B.andPraturlon, A. Crescenti, U.,Ciancetti,C.F., Nanni, T., Rainone,M., Crescenti, U.,Ed.(1986).Lagrandefranadi Ancona Cotecchia, V. andDelPrete,M.(1984). The Cotecchia, V. (1997).Lagrandefranadi Ancona. Cotecchia, V. (1982).Phenomenaofgroundinstability “G. D’Annunzio”,Pescara,Italy, 71pp. Storia dell’ArchitetturaeRestauro,Università september 1994,DipartimentodiScienze, Association ofEngineeringGeology the InternationalCongress oftheInternational scale landslidesinItaly, gravitational slopedeformationsandlarge- Sorriso-Valvo, M.,eds.(1994).Deep-seated 83, 15-21. della reteidrografi I movimenti franosieglisconvolgimenti earthquake. Caen,1984, seated gravitational movement reactivated by (1984). The Bisaccia landslide:acaseofdeep Nazionale diGeotecnica grande franadi Ancona del1982. Semenza, E.andSorriso-Valvo, M.(1983).La F., Gentili,B.,Pambianchi, G.,Melidoro, Tazioli, G.S., Vivalda, P., Coltorti, M.,Dramis, vol. spec.,146pp. del 13dicembre1982. Idrogeologia terremoto del1783. Landslides mechanism November 1980,withreferencetotheevolutive Southern Italyaffected bytheearthquake of reactivation oflarge fl Convegni Lincei zonazione sismica-frane”,Roma,1996. Convegno “LastabilitàdelsuoloinItalia: New Delhi,10-15Dec.1982,8,151-164. 1980 inSouthernItaly. produced bytheearthquake ofNovember 23, Italiana C.N.R. Finalizzato “Conservazione delSuolo” e possibilitàdiintervento delProgetto , 4,73-102. Rendiconti dellaSocietàGeologia , . IVInternationalSymposiumon

2, 33-38. , 4,1-24. , 134,187-259. ca prodottiinCalabriadal Studi Geologici Camerti Geologia Applicata e Geologia Applicata ows inthepartsof , Spoleto,3,31-46. IV I.A.E.G.Congress Special Volumefor Documents BRGM XV Convegno , Lisboa, Atti dei ,

Dramis, F., Farabollini, P., Gentili,B.and Dramis, F. andBlumetti, A.M. Someconsiderations Dramis, F., Bisci,C.andFazzini, M.(1998).Una De Bosis,F. (1859).IlMontagnolo:studie Dramis, F. (1992).Ilruolodeisollevamenti Del Prete,M.and Trisorio Liuzzi,G.(1981).Risultati Del Prete,M.andPetley, D.J.(1982).Casehistoryof Del Prete,M.(1979).Rilievo geologicoe D’Elia, B.,Esu,F., Pellegrino, A. andPescatore, T.S. Dramis, F., Gentili,B,Pambianchi, G.and Aringoli, Geomorphology” (O.Slaymaker, Ed.),pp.199- Italy.Umbria-Marche Apennines, large-scale gravitational phenomenainthe Pambianchi, G. (1995).Neotectonicsand central Apennines (Italy). central Apennines active normalfaulting: anexample fromthe mantle upwelling,drainageevolution and Jackson, J.A.(2001).Interactionsbetween paleoseismology. about seismicgeomorphologyand 73-76. frana chiamataItalia. osservazioni. International spec. 1992/1,9-15. appenninico. tettonici alargo raggio nellagenesidelrilievo 153-165. 1980 (AV) mobilitatadalterremotodel23Novembre dello studiopreliminaredellafranadiCalitri 291-304. Italy the mainlandslideatCraco,Basilicata,South 15, 255-297. da frana Bomba conparticolareriferimentoalrischio geomorfologico dellespondedellagodi IV, 1943-1948. and Foundation Engineering International Conference onSoilMechanics induced bythe1980Italianearthquake. (1985). Someeffects onnaturalslopestability Camert,i versante adriaticomarchigiano. D. (2002).Lamorfogenesigravitativa nel s. 2,G.A.GabrielliEd.,Fano. . Geologia Applicata eIdrogeologia . Geologia Applicata eIdrogeologia . Geologia Applicata eIdrogeologia n.s. , 1,103-125. , 147,475-497. Enciclopedia Contemporanea Studi Geologici Camerti Tectonophysics Scienza Nuova Geophysical Journal , SanFrancisco, Studi Geologici , inpress. In “Steepland 24-05-2004, 15:24:35 , 1(4), , vol. , 17, , 16, , 7, , LARGE SCALE GRAVITATIONAL PHENOMENA IN SOUTHERN-CENTRAL ITALY: GEOMORPHOLOGICAL FRAMEWORK, TRIGGERING FACTORS,

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217, J. Wiley & Sons, Chichester. Dramis, F., Tropeano, D. and Turconi, L. (2002). Dramis, F., Garzonio, C.A. and Gentili, B.(1992). Piene torrentizie dell’ottobre 2000 nelle Deepening of hydrographic pattern and slope Alpi Nord Occidentali. Altri insegnamenti stability: some sliding phenomena in the Mio- sull’importanza dell’analisi geomorfologica Pliocene terrain of central southern Marche abbinata all’indagine storica nelle attività di (Central Italy). Geoöko Plus, 13 (1), 63-78. prevenzione. Atti dei Convegni Lincei, 181, Dramis, F., Genevois, R., Prestininzi, A., Lombardi, 13-32. F. and Cognigni, L. (1982). Surface fractures Faraone, D. and Stoppa, F. (1988). Il tufo di Orvieto connected with the Southern Italy earthquake nel quadro dell’evoluzione vulcano-tettonica (November 1980). Distribution and della caldera di Bolsena, Monti Vulsini. geomorphological implications. IV I.A.E.G. Bollettino della Società Geologica Italiana Congress, New Delhi, 8, 55-66. 107, 383-397. Dramis, F., Gentili, B, Pambianchi, G. and Aringoli, Favali, P. and Gasparini, C. (1985). Campi di stress D. (2002). La morfogenesi gravitativa nel nel bacino mediterraneo derivanti dallo studio versante adriatico marchigiano. Studi Geologici di meccanismi focali. III Convegno del Gruppo Camerti, n.s. 1., 103-125. Nazionale di Geofi sica della Terra Solida, Dramis, F., Gentili, B. and Pieruccini, U. (1979). Roma, 1984, 1169-1183. La carta geomorfologica del medio bacino del Gasparini, C., Jannaccone, G. and Scarpa, R. (1985). Tenna (Marche centro- meridionali). Geologia Fault-plane solutions and seismicity of the Applicata e Idrogeologia, 14 (2), 197-204. Italian peninsula. Tectonophysics, 117, 59-78. Dramis, F., Gentili, B., Rodolfi , G., Bisci, C., Di Genevois, R. and Prestininzi, A. (1979). Time- Eusebio, F. and Pambianchi, G. (1993). Ancient dipendent behaviour of granitic rocks related to and historic landsliding in villages of Marche their alternative grade. International Congress Region and of Tosco-Romagnolo Apennine. on Rock Mechanics, Montreux 1979, 153-159. In “Temporal Occurrence and Forecasting Genevois, R. and Prestininzi, A. (1982). Deformazioni of Landslides in the European Community”, e movimenti di massa indotti dal sisma del Final Report of The European Community 23.11.1980 nella media valle del F. Tammaro Programme, Epoch, Contract 90, vol. 2, 871- (BN). Geologia Applicata e Idrogeologia, 17 888. (2), 305-318. Dramis, F., Govi, M., Guglielmin, M. and Mortara, Genevois, R., Prestininzi, A. and Valentini, G. (1984). G. (1995). Mountain permafrost and slope Caratteristiche e correlazioni geotecniche dei instability in the Italian Alps. The case of the depositi argillosi bradanici affi oranti a NE della Val Pola landslide. Permafrost and Periglacial Fossa. Geologia Applicata e Idrogeologia 19, Processes, 6, 73-82. 173-212. Dramis, F., Maifredi, P. and Sorriso-Valvo, M. (1985). Giacomelli, L. and Scandone, R. (2001). Vesuvio, Deformazioni gravitative profonde di versanti. Pompei, Ercolano: Eruzioni e escursioni, BE- Aspetti geomorfologici e loro diffusione in MA Editrice, 127 pp. Italia. Geologia Applicata e Idrogeologia, 20 Govi, M. (1977). Photo-interpretation and mapping (2), 377-390. of landslides triggered by the Friuli earthquake Dramis, F. and Sorriso-Valvo, M. (1983). Two cases (1976). I.A.E.G. Bulletin, 15 67-72.

of earthquake- triggered gravitational spreading Govi, M., Mortara, G. and Sorzana, P.F. (1985). PR01 to B15 n° 1 - from Volume in Algeria and Italy. Rendiconti della Società Eventi idrologici e frane. Geologia Applicata e Geologia Italiana, 6, 7-10. Idrogeologia, 20 (2), 359-375. Dramis, F. and Sorriso-Valvo, M. (1994). Deep- Govi, M. and Turitto, O. (1992). La frana di Val seated gravitational slope deformations, related Pola del 1987 in Alta Valtellina. In “Frane landslides, and tectonics. Engineering Geology, e territorio” (A. Vallario, Ed.), pp. 392-414, 38 (3-4), 231-243. Liguori Editore, Napoli.

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi Guadagno, F.M. andPerrielloZampilli,S.(2000). Hutchinson, J.N.(1988).Morphologicaland Hutchinson, J.N.andDelPrete,M.(1985).Landslides Guadagno, F.M., Forte, R.,Revellino, P., Fiorillo,F. Guadagno, F.M. (2000). The landslidesof5thMay Guadagno, F.M. (1991).Debrisfl Hungr, O.(1995). A modelfortherunoutanalysisof Harris, Keefer, D.K.(1984). Lavecchia, G.(1988). The Tyrrhenian- 8 Dixon N.andIbsenM.L.Eds.),pp.671-676, in research,theoryandpractice”(BromheadE., (South ItalyonMay5-6,1998. invested Sarno,Quindici,SianoandBracigliano Triggering mechanismsofthelandslidesthat 5 to geologyandhydrogeology. geotechnical parametersoflandslidesinrelation by theearthquake of23 at Calitri,Southern Apennines, reactivated Geomorphology discontinuities andthedevelopment offailure. Region: theroleofmorphologicalslope initiation ofdebrisavalanches intheCampania and Focareta, M.(2003).Someaspectsofthe 470. Journal ofNepalGeological Society disasters oralsoman-inducedphenomena? 1998 inCampania,SouthernItaly:natural on SlopeStability volcano-clastic soil. Global andPlanetary Warming PermafrostinEuropeanMountains. F., Guglielmin,M.andPalacios, D.(2003). W., Sollid,J.L.,King,L.,Holmlund,P., Dramis, Canadian Geotechnics Journal rapid fl 225. Cardiff. 9-38. Idrogeologiae Geologia Applicata 296. seismotectogenesis. Apennines system:structuralsettingand Bulletin earthquakes.

th th C., Vonder Mühll,D.,Isaksen,K.,Haeberli, ISL International.SymposiumonLandslides , Lausanne,vol. 1,3-35. ow slides,debrisfl , 95,406-421.

Geological Societyof America inpress. , London,125-130. Landslidescausedby Tectonophysics International Conference Chang,e 33(3-4),215- ows, and avalanches. ow intheCampanian rd November 1980 32,610-623. Proceedings of In “Landslides 147,263- , 20(1), 22,463- ,. . Martini, E.andMargottini, C. (2000).Lefranestoriche Panizza, M.(1973). Glacio-pressureimplicationsin Pane, V. andMartini, E.(1997). The preservation Oddone, E.(1930).Ilterremotodell’AltaIrpinia. Müller, L.(1964).Rockslideinthe Vajont valley. Mazzolai, P. (1980).Esamepreliminaredell’infl Manfredini, G.,Martinetti,S.,Ribacchi,R.and Lunardi, P. andFornaro, M.(1980).Criteridiscelta Lotti, B.(1908).SullafranadiPortaCassiapresso Lentini, F. (1969).Facies estratigrafi Lembo Fazio, A., Manfredini,G.,Ribacchi,R.and area. the productionoflandslidesinDolomitic Balkema, Rotterdam. Sites” the Preservation ofMonumentsandHistoric Conference on“Geotechnical Engineeringfor case anditsobservatory. of historicaltowns ofUmbria:theOrvieto 29, 181-196. Bollettino dellaSocietàSismologica Italiana 148-212. Rock Mechanics andEngineeringGeology, Regione dell’Umbria,Perugia. Rupe diOrvietoedelColle Todi” (CD-Rom) di Todi eOrvieto. Geotecnica rupe diOrvieto. Sciotti, M.(1980).Problemidistabilitàdella 229. Nazionale diGeotecnica Orvieto eproposteoperative. per interventi diconsolidamentodellaRupe di Geotecnica franoso in Trentino. sistemazioni idraulichesuifenomenididissesto delle condizionipluviometrichee Geologico d’Italia Orvieto. Scienze Geologiche,529-556. di ScienzeNaturali inCatania Craco (Matera). pliocenici affi Toronto, Canada,vol. 2,115-120. Symposium onLandslide, instability intheOrvietoHill. Sciotti, M.(1984).Slopefailure andcliff (Viggiani C.,Ed.), pp.489-498,. Geologia Applicata e Idrogeologiae Geologia Applicata Bollettino delRegio Comitato , Firenze,1,231-246. oranti frailF. Agri elazonadi , Firenze,277-281. Atti dell’AccademiaGeoenia XIV Convegno Nazionaledi , 39(1),36-41. Publ. of“Osservatoriodella XIV Convegno Nazionale , Firenze1980,219- Proceedings ofthe September 1984, 4 s.7,1,Suppl. th XIV Convegno a e depositi dei a International 24-05-2004, 15:24:39 uenza , 8, 2, ,

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289-297. 406-422. Pantosti, D. and Valensise, G. (1990). Faulting Segrè, C. (1920) - Criteri geognostici del mechanism and complexity of the 23 November consolidamento della falda franosa del 1980, Campania-Lucania earthquake, inferred Montagnolo (litorale Ancona Falconara). from surface observations. Journal of Bollettino della Società Geologica Italiana, Geophysical Research, 95, 15319-15341. 38(3), 99-131. Pastori, L. (1781). Memorie istoriche della nobilterra Skempton, A.W. and Hutchinson, J. N. (1969). di Montelparo. Stamperia G.A. Paccaroni, Stability of natural slopea and embankment Fermo. foundations. 7th International Conference on Pialli, G., Martini, E. and Sabatini, P. (1978). Soil Mechanics and Foundation Engineering, Contributo alla conoscenza della Geologia Mexico, 3, 291-340. del Colle di Orvieto. Bollettino della Società Solonenko, V.P. (1977). Landslides and collapses in Geologica Italiana 97, 103-114. seismic zones and their prediction. Bulletin of Pierson, T.C. and Costa, J.E. (1987). A rheological the International Association of Engineering classifi cation of sub-aerial sediment-water Geology 15, 4-8. fl ows. Engineering Geology 7, 1-12. Sorriso-Valvo, M. (1979). Trench features on steep- Racioppi, G. (1889). Storia dei popoli della Lucania e sided ridges, Aspromonte, Calabria (Italy). della Basilicata. Ed. Loescher & C. Polish-Italian Seminar on Mass Movements, Reggiani, A. (1981). Ricerche di paleoclimatologia Warsawa 1979, 98-109. alpina e appenninica. Cicli climatici di piovosità Tinsley, J.C., Youd, T.L., Perkins, D.M. and Chen, e laghi di frana nell’alta valle del Camone in A.F.T. (1985). Evaluating liquefaction epoca storica. Studi Romagnoli, 32, 2-14. potential. U.S. Geological Survey Professional Regione Umbria (1990-91). Progetti esecutivi per Paper 1360, 263-316. il defi nitivo consolidamento della Rupe di Tommasi, P., Ribacchi, R. and Sciotti, M. (1986). Orvieto ai sensi della L. 545/87, Perugia. Analisi storica dei dissesti e degli interventi Revellino, P., Hungr, O., Guadagno, F.M. and Evans, sulla rupe di Orvieto: un ausilio allo studio della S.G. (2003). Velocity and runout simulation of stabilità dei centri abitati. Geologia Applicata e destructive debris fl ows and debris avalanches Idrogeologia, 21, 99-154. in pyroclastic deposits, Campania Region, Italy. Urciuoli, G.(1988). Tipizzazione geotecnica delle Environmental Geology in press. frane in Italia. Internal Report, Istituto di Riguzzi, F., Tertulliani, A. and Gasparini, C., 1989. Tecnica delle Fondazioni e Costruzioni in Study of the seismic sequence of Porto San Terra, University of Naples, 209-212. Giorgio (Marche) - 3 July 1987. Il Nuovo Valentini, G. (1979). L’evoluzione dei fenomeni di Cimento della Società Italiana di Fisica, sez. erosione nelle argille grigio-azzurre lucane in C, 12 (4), 452-466. una analisi areale tra i fi umi Bradano e Sinni. Ritsema, A.R. (1970). On plate tectonics in the Geologia Applicata e Idrogeologia 19 (3), Mediterranean. European Seismological 473-488. Commission General Assembly, Luxembourg, Valentini, G. (1995). Effetti di eventi meteorici in 5. ambiente di “Argille azzurre”. Atti dei Convegni Santacroce, R., Ed. (1987). Somma-Vesuvius, Lincei, 13, 75-94.

Quaderni de “La Ricerca Scientifi ca” 8, 243 Varekamp, J.C. (1980). The geology of the Vulsinian PR01 to B15 n° 1 - from Volume pp. Area, Lazio, Italy. Bulletin of Volcanology 43, Serva, L. (1981). Il terremoto del 1688 nel Sannio. 487-503. C.N.E.N., Roma. Vari, V. (1930). Il terremoto dell’alta Irpinia. Bollettino Segrè, C. (1919). Studio geognostico della falda della Società Sismologica Italiana 29. franosa del Montagnolo (Liitorale Ancona- Verri, A. (1905). Sulle frane di Orvieto. Bollettino Falconara). Giornale del Genio Civile, 57, della Società Geologica d’Italia 24, 31-32.

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Volume n° 1 - from PR01 to B15 B08 - B08 Leaders: F. Dramis,A.Prestininzi Westaway, R.andJackson,J.(1987). The earthquake Vinassa deRegny (1904).LefranediOrvieto. Volcanology andGeothermics (Southern Italy). of 1980November 13inCampania-Basilicata Giornale diGeologia Pratica Journal ofStructural 1,110-130. , 48,127-137. Zimmermann, M.andHaeberli, W. (1989).Climatic Universities, 52-66. regions of climaticchange: discussionreport on Alpine mountain areas. change anddebrisfl , Wageningen/Utrecht/Amsterdam Landscape-ecological impact ow activity inhigh- 24-05-2004, 15:24:42 Back Cover: fi eld trip itinerary

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