龙门山断裂带北段晚第四纪活动性讨论

2003-04-16,2003-11-20-2004B0017,1966,1/20(I-48-),(,100029),(TL)(ESR),,:-,;;,,,,:P315.2:A:0253-4967(2004)02-0248-110,(1),3050,NW,5070,10m100,500km,,,,,,(,1993)(),,(,1994;,1994),(Molnaretal.,1975;Tapponnieretal.,1977;Molnar,1989;Englandetal.,1990)2,Dewey(1973),Tapponnier(Molnaretal.,1975,1977,1978;Tapponnieretal.,1982,1990;Peltzeretal.,1988),,,,,26220046SEISMOLOGYANDGEOLOGYVol.26,No.2June,20041Fig.1TectonicsettingoftheLongmensanFaultzone.,-,,,(1993)(1994);(1999),,(TL)(ESR)1,,,,,--,,,;,--,,,;,,-,,,,,,,3,-;-;-(,1993)3,9421(,1994)2:(2a)2Fig.2MapshowingthestructureoftheLongmenshanFaultzone.a(F1)(F2)(F3)(F4,),();3,,,,b;b,,,-,--,(2)1.12,--;,11111--812km,,,50km,NWSE,,,,,,,(3a),TL,(8.4860.721)104a,8;23m(3b),,TL,(15.6741.322)104a,11112-,052263-Fig.3CrosssectionoftheBack2rangeFaultinBahai2Yuquanba.a:,,;b:,,;F,ÓTL,,,55,NW,76100m,,3m,,TL(1.1740.099)104a,,1.1,-,,78m,,,-,3050m,,(4a),TL(5.3780.457)104a,5,80m(4b),ESR,(42.223.2)104a,,(5),5022m,TL(3.2440.267)104aESR(57.015.9)104a,,,,256m,,1522:4-Fig.4CrosssectionofthePingwu2QingchuanFaultandthesamplinglocationsfordatingnearAnlehe.a:,,,,-,F,ÓTL;b:,,-,F,ESR5Fig.5CrosssectionoftheBack2rangeFaultandtheoverlyingterraceatShaojiaba.;;;;;;;F,ÓTL,ESR1.2--,,,,211211,,10m,12m(6)252266Fig.6CrosssectionoftheCentralFaultinthesouthofShuimogou.-;;;F11212,,NW,45,,(7a)ESR(99.234.9)104a,(7b)3m,TL(12.4830.725)104a,12,,,Q3p,,2,,7Fig.7CrosssectionofthesouthernbranchoftheCentralFault.a:,,F,ESR;b:,,,F,ÓTL1.3,,,,,3522:;,,20km,,,11311,,,(8a),,ESR(15.59.3)104a,,,,,(8b),,8Fig.8CrosssectionoftheFront2rangeFaultononesideoftheroadatDabakou.a:,(),F,ESR;b:,,F11312,8km,4050,NW,5070,,,11313,7080,N,,20km,,2,,,;,,;;50m,,45226;,,,,,2,,,,,?9Fig.9ActiveblocksaroundtheLongmenshanFaultzone.1;2;3;4-;5-;,,,,NW,,2,,,,,,-,(9)(2003),(2003),,,,,-,,N1520E,;NW-NS,2(,1993),(,1994),5522:,,.1994.()J.,16(4):404412.CHENShe2fa,DENGQi2dong,ZHAOXiao2lin.1994.Deformationalcharacteristics,evolutionaryhistory,anddeformationmechanismofthemiddleLongmenshanthrust2nappesandrelatedtectonics(I)J.SeismologyandGeology,16(4):404412(inChinese).,,.1994.J.,16(4):389403.DENGQi2dong,CHENShe2fa,ZHAOXiao2lin.1994.Tectonics,seismisityanddynamicsofLongmenshanMountainsanditsadjacentregionsJ.SeismologyandGeology,16(4):389403(inChinese).,.1993.M.:.TANGRong2chang,HANWei2bin(eds).1993.ActiveFaultsandEarthquakesinSichuanProvinceM.SeismologicalPress,Beijing(inChinese).,,,.2003.J.(D),33():151162.XUXi2wei,WENXue2ze,ZHENGRong2zhang,etal.2003.PatternoflatesttectonicmotionanditsdynamicsforactiveblocksinSichuan2Yunnanregion,ChinaJ.ScienceinChina(SerD),33(Suppl):151162(inChinese).,,.1999.J.,21(4):341345.YANGXiao2ping,JIANGPu,SONGFang2min,etal.1999.TheevidenceofthesouthLongmenshanFaultzonescuttinglateQuaternarystratumJ.SeismologyandGeology,21(4):341345(inChinese).,,,.2003.J.(D),33():1220.ZHANGPei2zhen,DENGQi2dong,ZHANGGuo2min,etal.2003.Activetectonicblocksandstrongearthquakesinconti2nentalChinaJ.ScienceinChina(SerD),33(Suppl):1220(inChinese).DeweyJF,BurkeKCA.1973.Tibetan,Variscan,andPrecambrianreactivation:ProductsofcontinentalcollisionJ.JourGeol,81:683692.EnglandP,MolnarP.1990.Right2lateralshearrotationastheexplanationforstrike2slipfaultingineasternTibetJ.Na2ture,344:140142.MolnarP,TapponnierP.1975.CenozoictectonicsofAsia:EffectsofcontinentalcollisionJ.Science,189:419426.MolnarP,TapponnierP.1977.RelationofthetectonicsofeasternChinatotheIndia2Eurasiacollision:Applicationofslip2linefieldtheorytolarge2scalecontinentaltectonicsJ.Geology,5:212216.MolnarP,TapponnierP.1978.ActivetectonicsofTibetJ.JourGeophyRes,83:53615375.MolnarP.1989.ThegeologicevolutionoftheTibetanplateauJ.AmericanScientist,77:350360.PeltzerG,TapponnierP.1988.Formationandevolutionofstrike2slip,rifts,andbasinsduringtheIndia2Asiacollision:AnexperimentalapproachJ.JourGeophyRes,93(B12):1508515117.TapponnierP,MolnarP.1977.ActivefaultingandtectonicsinChinaJ.JourGeophysRes,82:29052930.TapponnierP,PeltzerG,LeDainAY,etal.1982.PropagatingextrusiontectonicsinAsia:Newinsightsfromsimpleex2perimentswithplasticineJ.Geology,10:611616.TapponnierP,MeyerB,AvouacJP,etal.1990.ActivethrustingandfoldingintheQilianShan,anddecouplingbetweenuppercrustandmantleinnortheasternTibetJ.EarthPlanetSciLett,97:382403.65226LATEQUATERNARYACTIVITYANDAGECONSTRAINTOFTHENORTHERNLONGMENSHANFAULTZONELIChuan2youSONGFang2minRANYong2kang(InstituteofGeology,ChinaEarthquakeAdministration,Beijing100029,China)AbstractTheLongmenshanFaultzoneisanimportantthrustfaultontheeasternmarginoftheQinghai2TibetPlateau.TheCenozoicactivityofthefaultzonehasattractedgreatattentionofmanyscientistsathomeandabroad.TheLongmenshanFaultzoneconsistsoftheBack2range,theCentralandtheFront2rangeFaults,whichdifferfromeachotherinsizeandactivity.Meanwhile,theactivityofthewholefaultzoneischarac2terizedbysegmentation.PreviousstudiesonthemiddleandsouthernsegmentsofthefaultzoneshowedthatthesetwosegmentshavebeenactivesincelatePleistocene.However,littleworkhadbeendoneontheac2tivityofthenorthernsegmentofthefaultzonesofar.Inthisstudy,wemadeadetailedfieldinvestigationonthenorthernsegmentofth