简介：ThebookistheresultofajointmeetingoftheTectonicStudiesGroup,theMarineStudiesGroupandtheVolcanicandMagmaticStudiesGrouphostedbytheGeologicalSocietyofLondoninSeptember2001.Itis382pagesinlengthandconsistsofsixteenarticles,mostofwhichdescribeadifferentexampleofintraoceanicsubduction.Allthecontributionstothisvolumeareclearlypresentedandhavebenefittedfrompeerreviewandcarefulediting.

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简介：Adeep,narrow,anddistortedBenioffzone,plungingfromtheIonianSeatowardsthesouthernTyrrhenianbasin,istheremnantofalongandeastwardmigratingsubductionofeasternMediterraneanlithosphere.FromOligocenetoRecent,subductiongeneratedtheWesternMediterraneanandtheTyrrhenianback-arcbasins,aswellasanaccretionarywedgeconstitutingtheSouthernAoenninicArc.IntheTyrrhenianSea,stretchingstartedinlateMioceneandeventuallyproducedtwosmalloceanicareas:theVavilovPlainduringPliocene(inthecentralsector)andtheMarsiliPlainduringQuaternary(inthesoutheasternsector).Theyareseparatedbyathickercrustalsector,calledtheIsselBridge.Back-arcexten-sionwasrapidanddiscontinuous,andaffectedalandlockedareawherecontinentalelementsofvarioussizesoccurred.DiscontinuitiesinextensionweremirroredbychangesinnatureofthelithospherescrapedofftoformtheSouthernApenninicArc.PartofthetectonicunitsofthesouthernApennines,accretedintothewedgefromlateMiocenetoPliocene,hadoriginallybeenlaiddownonthinnedconti-nentallithosphere,whichshouldconstitutethedeepportionofthepresentslab.AfterPlio-cene,onlyIonianoceaniclithospherewassubducted,becausethelargebuoyancyofthewideandnotthinnedcontinentallithosphereofApuliaandAfrica(Sicily)preservedtheseelementsfromrollbackofsubduction.AfterPliocene,thepassivelyretreatingoceanicslabhadtoadjustanddistortaccordingtothegeometryofthesecontinentalelements.ThelateonsetofarcvolcanisminrespecttothedurationofextensionintheTyrrhenian-Ioniansystemmayfindanexpla-nationconsideringaninitialstageofsubduc-tionofthinnedcontinentallithosphere.ThestrongPleistoceneverticalmovementsthatoccurredinthewholesoutheasternsystem(subsidenceintheback-arcbasinandupliftintheorogenicarc)mayinsteadberelatedtothedistortionoftheoceanicslab.

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简介：Continentsubductionisoneofthehotresearchproblemsingeoscience.Newmodelspresentedherehavebeensetupandtwo-dimensionalnumericalmodelingresearchonthepossibilityofcontinentalsubductionhasbeenmadewiththefiniteelementsoftware,ANSYS,basedondocumentaryevidenceandreasonableassumptionsthatthesubductionofoceaniccrusthasoccurred,thesubductionofcontinentalcrustcantakeplaceandtheprocesscanbesimplifiedtoadiscontinuousplanestraintheorymodel.Themodelingresultsshowthatitiscompletelypossibleforcontinentalcrusttobesubductedtoadepthof120kmundercertaincircumstancesandconditions.Atthesametime,thesimulationsofcontinentalsubductionunderasingledynamicalfactorhavealsobeenmade,includingthepullforceofthesubductedoceaniclithosphere,thedragforceconnectedwithmantleconvectionandthepushforceofthemid-oceanridge.Theseexperimentsshowthatthedragforceconnectedwithmantleconvectioniscriticalforcontinentsubduction.

简介：Basedontheanalysesofgroupedactivityfeaturesofdeep-focus(M≥6.0)andshallow-focus(Ms≥5.0)earthquakesintheNortheastChinaregion,thetime-spacecorrelationbetweendeepfocus'strongearthquakegroup'andshallowfocus'strongearthquakegroup'havebeenstudied.ThestudywasmainlyonthecharacteristicsofearthquakedistributiononthecollisionzonebetweenthewestPacificplateandtheEurasianplateandonitsrelationstothemorphologicalfeatureofthewesternPacificsubductionzone.Moreover,emphasiswaslaidonanalysisoftheeffectofthewestPacificplateontheseismicityofEurasianplate.ItisshownthatintheregionwherethewestPacificplatesubductsatlowangles,theseismicityontheplatecollisionzoneisstrong,theeffectofplatesubductiononEurasiancontinentisstrongtoo,andthesubductionzoneisunderastateofhighcompressionalstress.However,intheregionwherethewestPacificplatesubductsathighangles,theseismicityalongtheplatecollisionzoneisweak,theeffectofplatesubductiononEurasiancontinentisweaktoo,andthetensilestressproducedbythesubductionzoneatdepthisenhanced.WethereforeproposethattheseismicityinthenortheastChinaregionwillenteranactiveperiodofshallow'strongearthquakegroup'inthefuture10years.Intheperiod,sixearthquakesofMs≥5.0mayoccur.Therefore,theworkofearthquakemonitoringandpredictioninthisregionshallbestrengthened.

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简介：在南方印度洋的年度subduction率被分析数据吸收(苏打)在19502008的时期输出的简单海洋计算。为潜在的密度班的subduction率普查在南方印度洋副热带的旋回的西南的部分显示出相应于印度洋副热带的模式水(IOSTMW)的一座山峰。混合层深度越深，在现在的气候学的混合层前面和联系相对更快的发行量越sharper导致了更大的侧面的正式就职，它首先dominantsIOSTMWsubduction率，当时与从垂直的抽的仅仅次要的贡献。没有概论的损失，通过在最小的垂直温度坡度(LMVTG)的层的水特征的小心的分析，作者建议IOSTMW作为thermostad被识别，与低潜在的涡度的侧面的最小(PV，吗不到200湯漠?敌????猯'T￣牯嘠污猼扵?????汁?桴獥??晲捡楴獮栠摡猠杩楮楦慣瑮愠瑣癩瑩?湡?瑳'L汩瑩?景攠畭獬晩捩瑡潩?湵敤?慶楲畯???牦浯??琠?㈱??琠浥数慲畴敲爠湡敧?牦浯㈠‰潴ㄠ?讬鶝??顟????醰??????颮鑈？？

简介：IntheDiegodeAlmagroarchipelagoofsouthernChile,aquartzrichmicaschistandamylonitizedgranitecontainLateJurassiczirconsofca166and170Marespectively.TheserocksweremetamorphosedduringtheCretaceousinasubductionzoneenvironment,whichdevelopedblueschistassemblagesinmetabasaltsinterleavedwiththemicaschist.ThedatedrockswereprobablypartoftheacidlargeigneousprovincedevelopedinsouthwesternGondwanalandduringtheextensionalphasewhichprecededthedismemberingofthesupercontinent.Theyconstituteevidencethattectonicerosionofthemarginoccurred,asthesesiliceousigneousrocks,formedintheSouthAmericanupperplate,weretransportedinthesubductionzonetosome20kmdepthpriortotheirexhumation.TheserocksareintectoniccontactthroughtheSenoArcabuzshearzone,withlatePermianturbiditesoftheDuquedeYorkcomplex,whichdidnotundergoblueschistmetamorphism.

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简介：CenozoicadakiticrocksintheGangdesechan-gedfrombarrencontinentalmeltstoore-formingslabmeltsat-23Ma.Thedistributionandchemicalcharac-teristicsoftheore-formingadakitespointtoanassociationwiththeNinetyeastRidge.Thesubductionofthethick,rigidNinetyeastRidgechangedthegeometryandrheologyoftheeasternTibetanPlateaulithosphereandastheno-sphere,restrainedtheeastwardescapeofasthenosphericmantleaswellascontinentalfragments,andpromotedtheupliftandbuildingoftheTibetanPlateau,whichconse-quentlychangedthetectonicandclimaticregimesineasternAsia.

简介：PlatesubductiondrivesboththeinternalconvectionandthesurfacegeologyofthesolidEarth.Despitetherapidincreaseofcomputationalpower,itremainschallengingforgeodynamicmodelstoreproducethehistoryofEarth-likesubductionandassociatedmantleflow.Here,basedonanadaptiveapproachofsequentialdataassimilation,wepresentahigh-resolutionglobalmodelsincethemid-Mesozoic.ThismodelincorporatesthethermalstructureandsurfacekinematicsoftectonicplatesbasedonarecentplatereconstructiontoreproducetheobservedsubductionconfigurationandEarth-likeconvection.Introductionoftemperature-andcomposition-dependentrheologyallowsforincorporationofmanynaturalcomplexities,suchasinitiationofsubductionzones,reversalofsubductionpolarity,anddetailedplate-boundarydynamics.Theresultantpresent-dayslabgeometrywellmatchesBenioffzonesandseismictomographyatdepths<1500km,makingitpossibletohindcastpastsubductiondynamicsandmantleflow.Forexample,themodelproducesaflatFarallonslabbeneathNorthAmericaduringtheLateCretaceoustoEarlyCenozoic,afeaturethathasbeengeodynamicallychallengingtoreproduce.Thishigh-resolutionmodelcanalsocapturedetailsofthe4-Devolutionofslabsandtheambientmantle,suchastemporallyandspatiallyvaryingmantleflowassociatedwithevolvingslabgeometryandbuoyancyflux,aswellastheformationofshallowslabtearsduetosubductionofyoungseafloorsandtheresultingcomplexmantledeformation.Suchageodynamicframeworkservestofurtherconstrainuncertainplatereconstructioninthegeologicalpast,andtobetterunderstandtheoriginofenigmaticmantleseismicfeatures.

简介：Wepresentnewgeochemicaldatafortheuppermantleandcrustalsections(whole-rockmajorandtraceelementcompositions)aswellasmineralchemicaldata,fromtheNorthernCarbibbeanophiolitesintheHabana-MatanzasregioninWesternCuba.TheseophiolitesarepartoftheNorthernCubanOphioliticBelt(NCOB),extendingformorethan1000kmalongtheisland.Theuppermantleperidotitesarecomposedmainlyofrefractoryharzburgitewithtectonitetextures,andshowconvex-downwardpatternsdepletedinMREEnormalizedtochondritevalues(McDonoughandSun,1995).Thesegeochemicaltrendsarecharacteristicfordepletedmantlewedgeperidotitesmetasomatizedbyslab-derived,LREEenrichedmelts.TheNCOBalsoincludesabyssalperidotiteshavinglowerLREE/HREEratiosanddisplayingrelativelyhomogeneousandflatpatternsfromMREEtoHREE.Theseperidotitesrepresentfragmentsaccretedintothecontinentalmarginfromasubductedoceaniclithosphere.GabbroanddoleriteunitsintheNCOBaresystematicallydepletedinHighFieldStrengthElements(HFSE:Nb,Ta,Hf,Ti)andREEwithrespecttoN-MORB(<1XN-MORB).Theirmeltevolutionwasaffectedbysubductioninput.Spatiallyassociatedgraniticrockshaveavolcanicarcgeochemicalaffinity.SomemaficextrusiverockswithintheNCOBexhibitboniniticsignatures,andmayrepresenttheproductsofsubductioninitiationmagmatism,whereasotherextrusiverockoccurrencesdisplayN-MORBtoE-MORBgeochemicalfingerprints,slightlymodifiedbysubductionderivedfluids.Usingthesegeochemicaldataandconstraints,wepresentatectonomagmaticmodelfortheevolutionoftheNCOBwithintheframeworkoftheCaribbeangeology.

简介：Weaddresstheroleoftheconcaveandconvexarcs(asobservedfromthesubductingplate)onthedeformationoccurringalongtheMyanmar-Andaman-Sumatramargin.Wecategorizethepre-andpost-seismicdeformationsofthelithosphereusingearthquakedatabaseoccurringeitherpriorto26thDecember2004M_w9.3off-Sumatramega-eventoraftertheincidence.Analysisunderpre-seismicdomainshowsthatareanearSumatrarecordshighestseismicity,whichlargelydropsintheareapasttheNorthAndaman,andfurtherincreasestowardsnorth.Shallowestdepthandminimumdipofthesubductinglithosphereisrecordedatthecentralsegmentwherethearctransformedintoconcaveshape.TheannualmomentenergyreleaseduringearthquakedecreasestomorethantwoordersofmagnitudepasttheNorthAndamantowardsnorthunderpost-seismicdeformationphase.HigherdepthsofcontinuityofeventsarepresumablyassociatedwithmoredippingBenioffzonesinboththeIndo-MyanmarandAndaman-Nicobarconvexarcs.Theseobservationsobviouslyaccountfortectonicsubdivisionofthemarginnearconcaveshapearcaroundthecentralpart.Absenceofvolcanism,presenceofsplayfaultsintheback-arc,sharpreductioninseismicitynearcentralsegmentareinterpretedtobecausedbymajortectonicimpactoftheNNE-wardconvergingbuoyantNinety-eastRidgeagainsttheAsianPlate.Shallowestdip,smallelasticthickness,weakconvergingIndianlithosphere,andevidencesofseriesofen-echelonblocksofftheeasternsideofthebrokennorthernNinetyeastRidgemightbeincapableofgeneratinggreatearthquakeinthisarea.

简介：EarthquakeeventsfromtheIndonesiansubductionzonerecordedinnorthernAustraliashowalongandhigh-frequencycodaassociatedwithbothPandSwaves.RegionaleventsrecordedbyWarramungaarrayinnorthernAustraliacanseparateoutwavepropagationthroughthemantlebyfocusingonthecoherentsignalacrossthemedium-aperturearray.Mostoftheincoherentwavecomponentsresultfromstructuresinthevicinityofthearraywithsmall-scalelengthsof1–2kmorsmaller.Thecoherentphaseswithrelativelyrapidchangesinwaveformsareassociatedwiththescatteringofseismicwavesbycrustalandmantleheterogeneity,butinsomecasecanberelatedtostructuraleffectsnearthesource.Asthedepthofthesourceincreases,thecoherentportionoftheseismicwavefieldtendstobecomemuchsimpler,whichsuggeststhattheheterogeneitytendstoweakenatdepthwithlarger-scalelength.WecomparethecoherentsignalfeaturesofearthquakesfromtheIndonesiansubductionzonethathaveoccurredinrecentyearswiththoseintheearly1980s,firststudiedbyKennett(PhysEarthPlanetInter47:319–332,1987).Thegeneralcharacteristicsofthecoherentsignalvariationwithdepthinrecentyearsarethesameasthoseobservedin1980s,butthevariationsarelarger.Thischangesuggestsastringervariationinheterogeneitywithdepththanbefore,whichmaybearimportantinformationaboutthedynamicprocessesandevolutionofthecrustanduppermantle.

简介：TheX-discontinuity,whichappearsatthedepthofapproximately300km,isanimportantseismicinterfacewithpositivevelocitycontrastsintheuppermantle.Detectingitspresenceandtopographycanbeusefultounderstandphasetransformationsofrelevantmantlemineralsunderthehigh-temperatureandhigh-pressurecircumstanceoftheEarth'sinterior.Inthisstudy,wedetecttheX-discontinuitybeneaththeRyukyusubductionzoneusingfiveintermediate-deptheventsrecordedbythedenseAlaskaRegionalNetwork(AK).TheX-discontinuityissuccessfullyrevealedfromtherobustslantstackingofthesecondarydown-goingandconvertingSdPphases.Fromthedepthdistributionofconversionpoints,wefindthattheX-discontinuity'sdepthrangesbetween269kmand313km,withanaveragedepthof295km.Alltheconversionpointsarelocatedbeneaththedown-dippingsideofthePhilippineSeaslab.Fromenergycomparisonsinvespagramsforobservedandsyntheticseismograms,thestrongconvertedenergyismorelikelyfromathinhigh-velocitylayer,andtheS-wavevelocityjumpsacrosstheX-discontinuityareupto5%to8%withanaverageof6.0%.Accordingtopreviouspetrologicalandseismologicalstudies,theX-discontinuitywedetectedcanbeinterpretedasthephasetransformationofcoesitetostishoviteineclogiticmaterialswithintheoceaniccrust.

简介：SoutheasternChinacoversanextensiveareafromthelowerreachesoftheYangtzeRivertothesoutheastcoastofChinamainland.OneofitsmaingeologicalfeaturesistheextensiveJura-Cretaceous(Yanshanian)magmatismandrelatedmetallogenesis.Recently,someresearchersadvocatethemantleplumemodelasanexplanation,butalloftheirevidencesaretooambiguous.

简介：Thehigh-pressuremetamorphosedGridinodykeswarmcomprisesamajorgroupofMesoarchean2.87-2.82GamaficdykesintrudedwithintheMesoarcheancontinentalcrustoftheKolacraton(theBelomoriantectonicprovince

简介：Calc-alkalinegranites(excludingA-andM-type)couldbedividedintotwopetrogenicseries,I,e,thesyntexisseriesandthetransformationseriesaccordingtotheirgeneticmechanisms.InthelightofthisclassificationwefoundthatgranitesofthesetwoseriesoftenaligneinpairedzonesparalleltocontemporaneousB-typeorintracontinentalcompression-subductionzoneswithinascendedslabs,re-sultinginaregularzonalpatterntogetherwithsubductionzones.Thus,theyaredefinedastwingranitebelts.Accordingtothespatialrelationsbetweenthegranitebeltsandthesubductionzones,thetwingranitebeltscouldbeclassifiedasA,ABandB-type.ThezonationofgranitesofthetwoseriesinthenorthernpartoftheEastQinlinareacouldbecitedasatypicalexampleofA-typetwingranitebeltsrelatedtotheYenshanianintracontinentacompression-subductionmovementinthearea.InthispaperthetectonicsettingsandpetrogenicfeaturesofthetwingranitesbeltsinEastQinlinaresystematicallydescribed,andatectonicmodelforgraniticmagmagenesisinintracontinentalcompression-subductionenvironmentshasbeenproposed.Inthismodeltheforma-tionofA-typetwingranitebeltsiscloselyconnectedwithtectonicmovementsintermsoftheprince-ple,ruleanddynamicsofmaterialdifferentiationinthelithosphere.