简介:<正>ONSOUTHERNSTRETCHOPTHES-NTECTONICBELT,CHINAChenGuanghaoandWeiZhoulin(ChangshaInstituteofGeotectonic,AcademiaSinica,Changsha,410013,Hunan,China)S-Ntectonicbelt,southstretching,boundingbeltItcanbeinferredfromthegeophysicaldata,linearstructures,tectonicevolu-tionhistoryandmetallogenythattheS-NtectonicBeltstretchesfurthersouthinadifferentdi-rectionandmannerafterinterceptedbytheRedRiverFault,Thestretchingsegmentistheim-portanttectonicboundaryinIndo-AsiaandassiminlatestheS-Ntectonicbeltwithsomediffer-ences.
简介:Themultivariatestatisticalanalysisisprofitablyapplicabletothestudyofconodontmultielementtaxonomy.R-modeclusteranalysesofquantitativeand0-1dataarecarriedoutheretoclassifymorethan6000discreteLowerTriassicconodontspecimensbelongingto108kindsofconodontelementsfromWesternGuangxi.TheresultsofR—modeclusteranalysisrevealmoredirectlytherelationshipamongmanyisolatedconodontelements,andtheyalsoprovethatthere-sultsofthelogicalinferencearebasicallycorrect,i.e.108kindsofconodontelementscanbeidenti-fiedinto32speciesbelongingto11generaofconodonts.TheapplicationofR-modeclusteranalysismultielementtaxonomybythemethod,hasbroughtabout4significantconclusions,whichcanbeusedbyconodontresearchersasreference.
简介:Anovelautomaticseamlessstitchingmethodispresented.Comparedtothetraditionalmethod,itcanspeedtheprocessingandminimizetheutilizationofhumanresourcestoproducegloballunarmap.Meanwhile,anewglobalimagemapoftheMoonwithspatialresolutionof~120mhasbeencompletedbytheproposedmethodfromChang’E-1CCDimagedata.
简介:TheJiamusimcdianmassifislocatcdaboutlittlcXinganlingtoLaoycling,casternHeilongjiangProvince.Beinginaccordwiththediwathcory,thcJiamusipalaco-mcdianmassifdevclopspre-geosyn-clinlarchacansialiccrust.KhondalitescricsinthcJiXidistrictmaybcrcputcdasrcprcscntivc,isotopicageofwbichis25OOMa.ThcrcarethcDongfc
简介:Thisstudyisthefirsttoreporttheradiocarbonages,mineralogical,morphological,geochemicalandstableisotopecompositionsofcalcretesfromNeogenesedimentsaroundlakesEymirandMoganintheG?lba??BasinofCentralAnatolia.MorphologicallydifferentformsofcalcretesintheG?lba??Basinincludepowdery,nodular,fractureinfill,laminarandhardpantypes.Calciteisthedominantmineralofcalcretecompositions;thediagnosticfeaturesofdessicationcracks,randomfractures,MnOliningsanddensespariticinfillingsareobserved.Chemicalanalysesshowaridconditionswithmeanannualprecipitationof<50mm.δ13Ccompositionsofthecalcretesrangefrom-6.77‰to-9.32‰PDB,typicalformostpedogeniccalcretes,reflectingthedevelopmentunderseasonallyaridclimatesandC3-dominatedvegetationcover.δ18Ovaluesarebetween-5.57‰and-7.80‰PDB,indicatingtheformationfrommeteoricwaterinavadosezoneenvironment.TheresultssuggestthattheMiddlePleistocenewasariderandwarmer,favouringtheformationofpalygorskiteinassociationwiththedifferentformsofcalcreteoccurrences,whereastheLatePleistocenewasdryerandcooler,supportingthedevelopmentofcalcretes.
简介:在这研究,在Tang-eKushk和Sarvestan区域stratigraphic节的东方的Tarbur形成的465m被学习,185薄节被提供并且分析。基于岩石层位学的研究,在这二stratigraphic节的Tarbur形成被划分成上面、更低的部分。更低的部分包括是的中等床的rudist石灰石与Gastropoda由铁小瘤组成。上面的部分用轻灰巨大的organodetrital石灰石做的。两个都学习的节的识别有孔虫目动物由组成:Orbitoides媒介,Orbitoidestriangularis,Orbitoidestissoti,Orbitoidesorientalis,Orbitoidesapiculata,Antalynakorayi,Rotaliaskourensis,Dicyclinaschlumbergeri,Nezzazatinellasp,Omphalocyclusmacroporus,Trochospirasp,铁陨石calcitrapoides,Broeckinellasp,Lepidorbitoidessocialis,Gavelinellapertusa,被检测,并且也,它有Salpingoporelladinarica的Dasycladacea,Salpingoporellaturgida,Salpingoporellasp...根据诊断有孔虫类,Tarb的年龄决心
简介:这研究在Balong提供n链烷和Holocene黄土的花粉记录()镇,Dulan()县,Qinghai()省,和环境变化从同意很好的两个记录重建了。过去的气候变化的三个阶段被n链烷和花粉代理的变化译解。在5370一BP前,气候温暖干燥却稍微潮湿,相应于Mid-Holocene气候的最佳;53703830一BP,气候或者变化了在之间温暖干燥稍微潮湿、温暖干燥,从Mid-Holocene气候的最佳显示转变到迟了的Holocene冷时期;在3830一BP以后,气候主要是温暖干燥的。温暖的凉爽、极其干燥的气候被n链烷和花粉代理在30402600一BP期间记录,建议环境演变为荒芜或咸的湖,根据在西方的周王朝的冷、高度经常的自然灾难时期(ca。29962721一BP)在中国。
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简介:ObjectiveThenearlyparallelN–S-trendingriftsinsouthernTibetrepresenttheE–WextensionoftheTibetPlateau.MostdatawhichconstrainedtheageoftheextensionaldeformationcomefromisotopicdatingofthedikesprobablyrelatedtotheactivityofthenearlyN–Sfaultingandmicasfromhydrothermalactivityandthelowtemperaturethermochronologyofplateauuplift.Previous
简介:ThetransitionzonebetweentheEastAsiaandCentralAsiacrustobodlesisnotonlyadiwaregion,butalsoagigantictectono-metallogenicbeltinAsia.IttrendsN-S,liesbetweenlong.100°-107°Eandlat.14°-62°N,hasalengthof4600kmandfurtherextendssouthwardandnorthward.Themainfeaturesofthebeltareasfollows:(1)Thebc1tcon8istsofotc
简介:In1997,IGCPProjectNo.410wasestablishedtoappraiseknownrecordsofOrdovicianbiotas,inordertoevaluateoneofthegreatest-everdiversificationsoflifeonEarth,between489and443millionyearsago.Datacollectionandanalysisofbiodiversitywerecoordinatedthroughsevenregionalteams,andaglobal“clade”team.
简介:经过几代人的工作,北京平原地质工作取得了丰硕的成果,在基础地质、水文地质、工程地质和环境地质等领域都有重要进展。本文通过北京平原三维地质结构分析,认为北京平原的地下水资源、工程地质、地面沉降、地裂缝灾害等地质问题均受三维地质结构控制,各种地质现象都处在一个统一的地质系统之内。第四系三维结构控制着第四系孔隙水资源的赋存、平原的工程地质特征和地面沉降的分布和演化;基岩的三维结构控制基岩裂隙水、岩溶水资源和地热资源的赋存状态;平原隐伏断裂对平原的地貌、基底形态起控制作用,对地裂缝,地面沉降等地质灾害的形成和发展有重要影响。这些由三维地质结构控制的地下水子系统,隐伏断裂子系统以及工程地质、地面沉降等地质问题,共同组成了北京平原区地质系统。