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简介：Basedonaquantitativeanalysisofforaminiferain39surfacesamplesoftheBeringandChukchiSeas,thenearlyabsenceofplanktonicforaminiferainthesurfacesedimentscanberelatedtothelowsurfaceprimaryproductivityandstrongcarbonatedissolutioninthestudyarea.Ithasbeenrevealedthatthesurfaceprimaryproductivity,andcarbonatedissolutionandpropertiesofwatermassesrelatedtothewaterdepthmainlycontrolthedistributionofbenthicforaminifera.TheshelfoftheChukchiSeaisdominatedbytheElphidiumspp.AssemblageandNonionellarobustaassemblagewithlowforarniniferalabundanceanddiversity,whichiscontrolledbythecoastalwatermassoftheArcticOcean.TheslopeoftheBeringSeaisdominatedbytheUvigerinaperegrina-GlobobuliminaaffinisassemblagewithabundantN.Robusta,andrelativelyhighforaminiferalabundanceanddiversity,whichiscontrolledbytheintermediateanddeepwatermassesofthePacificOcean.However,theBeringSeahasrelativelyshallowcarbonatelysoclineandcompensationdepth(CCD),atabout2000and3800m,respectively.Inaddition,thereexistsStetsoniaarcticainthesurfacesedimentsoftheupperslopeintheBeringSea,whichisatypicaldeep-seabenthicforaminiferalspeciesoftheslopeintheArcticOcean.ThisindicatesthatthedeepwaterofthetwoseasbesidetheBeringStraithadeverexchanged.

简介：Integratedstudiesofverticalsedimentarysequences,grainsizes,andbenthicforaminiferaandostracoda,incombinationwithAMS14Cdating,and210Pband137CsanalysiswerecarriedoutinthreevibracorestakenfromtheareaofrelictdepositsonthewesternSouthYellowSea.Therelictsands,whichareabout0.4mthick,overlieontheEarlyHolocenecoastalmarshortidalflatdepositswithanevidenterosionalinterfaceinbetween.Themiddleandupperpartsorsometimesthewholeoftherelictsandshavebeenreworkedunderthemoderndynamicenvironment.Thesedimentationratevariesbetween0.20–0.30cmyear-1.Therelictsandsshowabimodalgrain-sizedistributionpatterninfrequencycurves,withasharppeakinthecoarsefractionbetween3Φand4Φandasecondarypeakinthefinefractionofabout7Φ.Ofthebenthicforaminiferalandostracodassemblages,thereworkedrelictsandsarecharacterizedbythemixingofthenearshoreeuryhalineshallow-waterspeciesanddeeperwaterspecies.TheerosionalinterfaceatthebottomoftherelictsandsisconsideredasaregionalravinementsurfaceformedduringthetransgressionintheEarlyHoloceneduetoshorefaceretreatinglandwards.Therelictsandswereaccumulatedontheravinementsurfaceduringthetransgressioninthedeglaciationperiodaslagdepositsafterwinnowingandreworkingbymarinedynamicprocesses.Andthesecondarypeakoffinefractioninthefrequencycurvefortherelictsandssuggeststheinputoffine-grainedsedimentsduringthereworkingprocess.Astheconclusion,therelictsandsinthestudyareaareinterpretedasatypeofreworkedrelictsediments.

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简介：Palaeo水文学领域调查在Jinghe河的中间的活动范围被执行。一套palaeofloodslackwater存款床在河岸在Holocene黄土土壤顺序被识别。沉积样品从侧面，和粒子尺寸分发被收集，磁性的危险性，loss-on-ignition在实验室被分析。分析结果证明palaeofloodslackwater存款在Jinghe河山谷记录了非凡的洪水事件。根据stratigraphic关联并且OSL标明日期，palaeoflood事件被标明日期到41004000一BP。palaeoflood山峰分泌物被估计是由使用水文学模型的19,41022,280m3/s并且由不同途径检查。这些结果把Jinghe河的洪水数据顺序扩大了到10,000年的时间规模。它在Jinghe河排水盆为水力的工程并且为洪水危险的缓解提供了重要数据。

简介：Thispaperdescribestherelativecontentsofdominantdiatomspeciesandthedistributivecharacteristicsoftropicalpelagicspeciesanddiatomassemblages,andalsodiscussestherelationsbetweentherelativecontentoftropicalpelagicspeciesandKuroshioCurrentandbetweenthedistributionofdiatomassemblagesandmaterialsources.Theresultsshowthatthelimitof＞20%relativecontentoftropicalpelagicspeciesisbasicallyconsistentwiththedemarcationofKuroshioCurrent,andthatthedistributionsofdominantdiatomspeciesanddiatomassemblagesreservetherecordsoftheircloserrelationstomaterialsources.

简介：TheDevoniansuccessioninSouthChinaiswell-knownforitscompletedevelopment,vari-fiedsedimentarytypes,remarkablelithofaciesvariationandabundantmineralresources.TheSouthChinaplatewasformedbythecollisionandcollageoftheYangtzeplateandtheCathaysianplate.ThecollisionbeganapproximatelyattheJinningianstageandthecollagewasnotfinalizeduntiltheGuangxianmovement.ItwasontheSouthChinaplatewithasomewhatdifferentnatureofthebasementthattheDevoniandepositionformed.

简介：ObjectiveThedistributionofrearrangedhopanesinhydrocarbonsourcerocksisinfluencedbythermalmaturityandoriginalsourceinput,andisalsocontrolledbydepositionalconditions.Throughcomparisonoflacustrineandcoal-bearingsourcerocks,thisworkattemptedtoanalyzethecompositionandoriginofrearrangedhopanesinhydrocarbonsourcerocks.Takenthesourcerocksfrom

简介：Accordingtotheideasandconceptsofsystemsdynamicofcontinentstructure,usingpreviousinformationrelatedtothestudyarea,combininganalysesonorogenicbelt,basinandmagmaticrock,thepresentpapersynthesizesthetectono-sedimentarydevelopmentofsoutheasterncoastregion,China,withspecialemphasisonthemountainmaking,basiningandmagmafcactivity.ThetectonicevolutionafterLateCaledonianorogenywasdominatedbyalternatingriftingandconverging,subsidinganduplifting,mountainmakingandbasiningincentralandsouthernpartsofsoutheasternChinaandtheadjacentregionstotheeastandwest.Seventeengeologicevents,nineeventsofplateorterrainconvergence,andcontinentalcrustaccretion,aswellaseighteventsofintracontinentalriftingandbasinfaulting,arecloselyrelatedtothetectonicandsedimentaryevolutionofthestudyarea.Theaccompaniedintenseandfrequentsedimentation,folding,faulting,magmatismandore-formingprocessallowedhugecoal

简介：Aglobal-scaleglaciationoccurredatabout600Maago.Asaresult,theEarthbecamethe'SnowballEarth'.Theglaciationcametotheendabruptlywhenatmosphericcarbondioxideincreasedtosuchanextentastobeabout350timesthemodernlevelbecauseofsubaerialvolcanicdegassing.TherapidterminationofglaciationwouldhaveledtowarmingoftheSnowballEarthandextremegreenhouseconditionswouldhavebeencreated.Thetransferofatmosphericcarbondioxidetooceanswouldgiverisetotherapidprecipitationofcalciumcarbonateinwarmsurfaceseawaters,thusformingthecapcarbonaterocksasobservedworldwidetoday.Regionallypersisting,thinlayersofcarbonaterocksdirectlyandubiquitouslyoverlieProterozoicglacialdepositsalmostoneverycontinent,andarecommonlyreferredtoascapcarbonates.Theirunusuallitho-fabrics,stratigraphicallyabruptbasalandupper-levelcontactsandstronglynegativecarbonateisotopicsignatures(δ13Ccarb.valuesrangefrom-7.0‰-0‰)suggestachemicaloceanographicorigin,thedetailsofwhichremainunknown.Itisproposedthattheseenigmaticdepositsarerelatedtothedestabilizationofgaseoushydrateinterrestrialpermafrostfollowingrapidpostglacialwarmingandfloodingofwidelyexposedcontinentalshelvesandinternalbasins.Theauthorscarriedoutstudiesonthegeochemistry,sedimentologyandpalaeontologyoftheSiniancapcarbonatesinGuizhouandHunanprovinces,includingtheoccurrenceofcapcarbonatesofunusualfabrics,stronglynegativecarbonisotopicsignatures,andalotofbitumennodules.Fromtheresultsitissuggestedthatthecapcarbonateswereformedfromsolidmethaneseepage,anditisinagreementwithKennedy'sviewpoint(2001)thatthecapcarbonatesresultedfromtherapidprecipitationofcalciumcarbonateinresponsetosolidmethaneseepage.

简介：MiocenemarlisthemostwidespreadTertiarystratigraphicrecordinthenorthernTibetPlateau,termedtheWudaoliangGroupintheHohXilregionandthecorrelativeSuonahuFormationintheQiangtangregion.TheuniformmarloverliesredbedsoftheEocene-OligoceneFenghuoshanGroup.TheWudaoliangGroupisgenerally100-400mthick,butthethickeststrataare700-1300m,locatedintheHaidinghu(MaidingLake)andTuotuohe(TuotuoRiver)regionsrespectively.Basedonobservationsfromeightmeasuredsectionsandoutcrops,thethin-beddedmarl,whichvariesincolourfromgrey-whitetolightbrown-grey,isexplainedasalarge-scaleorseriallacustrinedepositstretchingthroughoutnorthernTibet.TheWudaoliangGroupcommonlycropsoutongeographiclowlandatanaverageelevationof4600mabovesealevelwithinthemountainchains,showingconcordantsummitlevels,e.g.theFenghuoshanandBairizhajiaMountains.Thesemountainswithaflatridgeareconsideredtoberemainsofthepalaeo-planati

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简介：TheupwellingareaintheChangjiangEstuarywasselectedtocollectthecore,wheretheredtideoccurredfrequentlyandhypoxicexisted.Thetotalorganiccarbon(TOC),totalnitrogen(TN),biogenicsilica(BSi)andstableorganiccarbonisotopicratios(δ13Corg)weredeterminedonthe210Pb-datedsedimentcore.TheconcentrationsofTOC,TN,BSiaswellastheirsedimentationfluxeshaveincreasedtosomeextentsincethe1970s.TOCandTNfluxesincreasedabout45%,36%respectively.Theaverageδ13Corgvalueinthecorewas-23.67×10-3whichremainednearlyconstantbeforethe20century.Theδ13Corgvaluesincreasedafterthe1900s,twomarkedincreaseswereobservedfromthe1950sandthe1970s.Asimpleδ13Corgmodelwasusedtoestimatethecontributionofterrigenousandmarineorganicmatterinputsforthesediment,whichindicatedtheincreaseinaccumulationsincethe1970shasbeenalmostexclusivelymarine.Theincreasingofmarineorganicmatteraccumulation(TOC,TNandBSi)wascorrespondingwiththeincreasingoffertilizerconsumptionandtheNO3-NbudgetsfromtheChangjiangRiver.Theriverinerunoffoffertilizersandnutrientsstimulatedthealgaeblooming.Enhancedprimaryproductionresultedinanenrichmentoforganicmatterinthesediment.ThesedatasupportthehypothesisthatanthropogenicnutrientloadinghasbeenasignificantfactorontheeutrophicationintheChangjiangEstuary.

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简介：沙的碎片流动存款在联合起来是在场的我在期间在华南海的Baiyun消沉的煤气的地A中新世。少量很好，数据和沉积microfacies的大可变性使识别并且预言主要煤气的水库的分发模式困难，并且严重妨碍了煤气的域的进一步的探索和开发。因此，充分利用可得到的地震数据为当构造三维的水库模型时，预言沉积microfacies的空间分发是极其重要的。当模特儿的策略或工作流由沉积microfacies和地震数据控制了的一座合适的水库被开发了。地震属性的五种类型被选择与平均数平方(RMS)振幅执行了的沙百分比，和根相关最好在RMS振幅和沙百分比之间的关系被用来构造一张水库沙分发地图。主要沉积microfacies的三种类型被识别：碎片隧道，扇子脑叶，和自然早朝。用从沉积microfacies边界的限制，一个沉积microfacies模型用顺序的指示物被构造并且分配了价值模拟方法。最后，为沙的碎片流动存款的物理性质的水库模型由沉积microfacies控制了，地震倒置数据被建立。因为从记载得好的解释的沉积microfacies和水库性质是内在地不同的，性质截止价值被采用。当基于沉积microfacies控制使用模拟方法时，适当水库性质截止的选择是在水库建模的关键步。当反常数据被截断，水库性质概率分发适合正常分布时，控制microfacies的水库性质模型比那些从顺序高斯获得模拟方法的是更可靠的。为碎片隧道，扇子脑叶，和自然早朝外形的有效的孔的截止分别地是0.2，0.09，和0.12；相应的平均的有效的孔是0.24，0.13，和0.15。建议当模特儿的方法充分利用地震属性和地震倒置数据，并且也与地质的意义使性质成为对正常分布更一致的单个井的depositionalmicrofacies的数据。因此，当我们构造沙的碎片流动的一个模型时，方法允许更可靠的输入数据的使用�

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简介：Porestructurecharacteristicsofrockareagreatconcernforresearchersandpractitionersinrockmechanicsandrockengineeringfields.Inthisstudy,mercuryintrusionporosimetry（MIP）wasusedtomeasureporesizedistribution,aswellasseveralimportantindexparametersofporestructure,forsevencommontypesofdeepsedimentaryrockswithatotaloffiftyrocksamples.Resultsshowasimilarporesizedistributionpatternoftherocksamplesinthesamelithologicalgroup,butremarkabledifferencesamongdifferentlithologicalgroups.Amongseveninvestigatedrocktypes,mudstonehasthesmallestporosityof3.37%,whileconglomeratehasthelargestvalueof18.8%.Itisalsofoundthattheporosityofrocktypeswithfinergrainsizeislowerthanthosewithcoarsergrainsize.Meanwhile,acomparisonoffrequencydistributionattenintervalsofpore-throatdiameteramongseventypesofsedimentaryrocksrevealsthatdifferentrocktypeshavedifferentdominantpore-sizeranges.Furthermore,permeabilityoftheinvestigatedsedimentaryrocksampleswasderivedbasedonMIPdatausingreportedtheoreticalequations.Amongsevenrocktypes,mudstonehasthelowestaveragedpermeability(3.64×10-6mD)whileconglomeratehasthehighestone(8.59×10-4mD).Frommudstonetoconglomerate,rockpermeabilityincreaseswithanincreaseofgrainsize,withonlyanexceptionofsiltstonewhichhasarelativelylargerporosityvalue.Finally,regressionanalysisshowthatthereisagoodfitting（R2=0.95）betweenpermeabilityandporositywhichcouldbeeasilyusedtoderivereliablepermeabilityvaluesofsimilarkindsofengineeringrocks.

简介：Detailedstudiesofpetrology,palaeocurrentdirection,paiaeogeomorphologyandpalaeohydrody-namicshavebeenconductedforthePermian-TriassicCangfanggouGroupintheforedeepoftheBogdaMountainsinthesoutheasternJunggarBasin,Xinjiang.Sedimentaryenvironmentsandfadesofalluvialfansandpebblybraidedrivers,sandybraidedrivers,meanderingrivers,low-sinuosityrivers,swampsandfresh-waterlakesarerecognizedinthegroup.Climateandtectonicsofsourceareasstronglycontrolledtheevolutionofthesedimentaryenvironmentsandfaciesintheforedeep.TheblockfaultingintheBogdaMountainsincreasedthegroundslope,whichledtoadrasticincreaseinthegrainsizeofthesediments.Humidclimate,beingbeneficialtoplantgrowth,wouldprovideprotectionofchannelbanksandatthesametimeweakenchemicalweatheringinthesourcearea,thuslargeamountsofclaymaterialsareavailablefortheformationofclayplugs.Asaresult,stablebanksandmeanderingriverbeltsare

简介：StudyofseismicactivityintheKuqaareaenablesustoinfersomepossibleactivefaultsinbasementfromtheePicentraldistributionondifferentprofiles.Therelationsbetweenactivefaultsinthebasementandsurfacestructuresareanalyzedandthedifferencebetweensedimentarycoverandbasementintheirdeformationcharacteristicsandthegenesisarediscussed.Thefollowingconclusionshavebeendrawn:(1)theepicentraldistributionindicatesthat,theeastQiulitagandsouthandnorthQiulitagdeepfaultsinthebasementcorrespondtotheeastandwestQiulitaganticlines,respectively.Moreover,deepfaultsalsoexistbeneaththeYiqiklikandYakenanticlines.Itindicatesthattheformationofsurfacestructuresiscontrolledbydeepstructures;(2)ANE-trendingstrike-slipfaultdevelopsalongthelinefromthewesternterminationofYiqiklikstructuretoDongqiuWell5andaNW-trendingactivefaultonthewesternsideofBaicheng.ThetwoactivefaultsacrossthetectonicstrikearethemaincausesfortectonicsegmentationoftheKuqadepressionandpossiblythecauseforthemiddlesegment(Kuqa-Baicheng)ofthedepressiontobemoreshortenedthanbothitseasternandwesternterminations;(3)Thedifferencebetweenthesedimentarycoverandbasementintheirdeformationcharacteristicsdependsmainlyonthedifferentpropertiesofmediabetweenthem.Thelithosphericstrengthofthebasementinthebasinisfairlyhigh,whichdeterminesthebasementdeformationtobemainlyofbrittlefractureseismicactivity.Whilethestrengthofsedimentarycoverislow,wherethereexistweakthinlayers,suchascoalandgyps.Undertheeffectofstrongtectoniccompression,thesedimentaryrocksmayundergostrongviscousorplasticflowdeformation;meanwhile,anaseismicdetachmentmaytakeplacealongtheweaklayers.