在岩溶洞穴中地质风险对文化遗产保护的评估

JournalofCulturalHeritage11(2010)250–258OriginalarticleGeologicalriskassessmentforculturalheritageconservationinkarsticcavesEnekoIriarte∗,MiguelÁngelSánchez1,AlbertoFoyo2,CarmenTomillo3Dpto.CienciaeIngenieríadelTerrenoydelosMateriales-InstitutoInternacionaldeInvestigacionesPrehistóricasdeCantabria,E.T.S.IngenierosdeCaminos,CanalesyPuertos,UniversidaddeCantabria,Avda.LosCastross/n,39005Santander,SpainarticleinfoArticlehistory:Received2mars2009Accepted29avril2009Availableonline25March2010Keywords:KarsticcaveCulturalheritageDamagepreventionHeritageconservationGeologicalriskKarstgeomorphologyabstractTheincreasingawarenessofsomelocalandinternationalauthoritieshaspromotedtheappearanceofnewlegislationandtherisingofresearchworksfocusedinthepreventionofdamagetotheculturalheritageinkarsticcaves.Nevertheless,karsticareasusuallyimplycomplexstudies,andauniversalmethodologyisverydifficulttoestablish.Thisworkexposesthebasicmethodologyforthegeologicalriskassessmentinarchaeologicalsiteand/orrockartbearingkarsticcavesgettingastrategythatprovidesflexibilitytoadjustspecificmethodsaccordingtotheconditionsofdifferentcases.Theintegrateduseofbasicgeological(mapping,petrology,stratigraphy...)andgeotechnical(rockmassqualityanalyticalmethodsandindexes)techniquesusedinengineeringgeologyisproposed.Thosetechniquespermitthegeologi-calcharacterizationoftherockmass,thehazardidentificationandtheanalysisandthegeologicalriskassessmentoftheresearcharea.Obtainedgeologicalriskareascouldbeincludedinprotectionareasthatcouldbeusedasthebasisfortheselectionoftheareaswherefurtherinvestigationsandtheapplicationofprevention/mitigationmeasureswouldhaveabettercost/benefitratio.Thegeologicalriskshouldbeconsideredtogetherwithothertyperiskevaluationsinordertodefineeffectiveprotectionareas.©2010ElsevierMassonSAS.Allrightsreserved.1.IntroductionEffortsfortheevaluationandconservationofculturalheritagearemainlypursuedbylocalmunicipalities,regionalorstateculturedepartmentsandinternationalauthorities,e.g.UnitedNations,promotingseveralinitiativesespeciallydirectedatspecificmonu-mentsandarchaeologicalsites.Thoseeffortsareoftenconcernedwithrestorationorconservation,butrarelywithpreventionofdamage.Thisprobablyisduetothefactthatthereisalmostnolinkbetweenknowledgeofenvironmentalimpactsandculturalheritage[1].Fortunately,inthelastdecadesandduetotheworkscarriedoutbyinternationalorganizationsastheUnitedNationsEducational,ScientificandCulturalOrganization(UNESCO),theincreasingawa-renessoflocalauthoritieshaspromotedtheappearanceofnewlegislationandtherisingofresearchworksfocusedinthepre-ventionofdamagetotheculturalheritage.Agoodexampleofthe∗Correspondingauthor.Presentaddress:Dpto.ArqueologíayAntropología,Ins-tituciónMilàiFontanals-CSIC,Egipciaques15,08001Barcelona,Spain.Tel.:[phone];fax:[phone].E-mailaddresses:[e-mail](E.Iriarte),[e-mail](M.Á.Sánchez),[e-mail](A.Foyo),[e-mail](C.Tomillo).1Tel.:[phone];fax:[phone]Tel.:[phone];fax:[phone]Tel.:[phone];fax:[phone].differentlevelauthorities’concernintheconservationofthistypeofculturalheritagecouldbefoundinSpain,wheretheCultureDepartmentsofthreedifferentspanishregions,thePrincipalityofAsturias,theAutonomousCommunityofCantabriaandtheBasqueCountry,inagreementwiththemunicipalitieswherethecavesarelocated,promotedtheinclusionof17rockartbearingcavesfromtheCantabrianCorniche(NorthernSpain)intheUNESCOWorldheritagelist[2].Thedecisionwastakenin2008,duringthe32ndConferenceoftheUNESCOandwarnsaboutsomerisksconcerningtheconser-vation:“however,inthecontextofthecontemporarydiscoveryandopeningofthecaves,complexriskshavearisen,relatedtothealterationofthephysical,geologicalandbiologicalconditionsofconservation”andadvisesthat“extremelyrigorousmanagementisrequiredtoensurethattherisksareeffectivelydealtwith”[2](p.182).Accordingly,theknowledgeofthegeologicalfeaturesandprocessesandtheassessmentofthegeologicalriskaffectingeachsitearenecessaryforacorrectdamagepreventionandconserva-tion.Partialstudiesofthattypewerealreadydoneinsomeofthosesites[3–12].However,themethodologyforacorrectassessmentofthepotentialdamageorriskindifferentsitesormonumentsisnor-mallynotwellestablishedinthelegislation,anddiffersindifferentadministrations.TheIUGS[13]andEinstein[14]inCatanietal.[1]espousesthatacompletestudyinordertocharacterizepotentialdestructivephe-nomenainastudyrelatedtorisk,shouldincludethefollowing“risk1296-2074/$–seefrontmatter©2010ElsevierMassonSAS.Tousdroitsréservés.doi:10.1016/j.culher.2009.04.006E.Iriarteetal./JournalofCulturalHeritage11(2010)250–258251definitionsteps”:1.Hazardidentificationandanalysis.2.Descriptionofindividualelementsatrisk.3.Analysisofvulnerability.4.Riskanalysis.5.Riskassessmentandmanagement.Thedevelopmentofthesephasesrequiresthesurveyofallgeomorphologicalprocessesaffectingthearea,theanalysisofthecharacteristicsofthearchaeologicalelements,thecalculationofriskandtheidentificationofthestructuralinterventionformitiga-tingriskorreducinghazard.Nevertheless,karsticareasusual