简介:ThereareobviousdifferencesinthemineralassemblageandmetamorphicP-TconditionsbetweentheeclogitesfromthenorthernandsouthernpartsoftheeasternDabieMountains.ThosefromthenorthernpartofthemountainsaredevelopedinAlpineperidotiteandgneiss.Theyhaveamineralassemblageofgarnet+diopsidewithnoquartz,andwereformedattemperaturesof600℃-740℃.Thosefromthesouthernpartaredevelopedingneissandmarble.Theyconsistofgarnet+omphacite+lessquartzandweremetamorphosedattemperaturesintherangeof650°-800℃.Thesedifferencessuggestthattheformermaybeformedduringthemetamorphismofthedeepsubductedoceaniccrust,whereasthelattermaybegeneticallyrelatedtothesubductionofthecontinentalcrustinthisarea.
简介:ItisanacceptedfactthatthemainsolidphasesupportforpotassiumintheSichuanBasinispolyhalite[K2MgCa2(SO4)4·2H2O]ratherthansylvineis(KCl)(GongDXetal.,2015).Themineraltypes,occurrencecharacteristicsandmetasomatismofthepolyhalitebearingore-bedwereidentifiedandtheoriginofthepolyhalitewasdiscussed.ThepolyhalitesampleswereobtainedfromthecoreofZ12,locatedinDalongVillage,Guang'anCityofcentralSichuan.Thesamplingdepthswere2974m(s-1),3023m(s-2)and3106m(s-3).Themicrobeamanalysisofback-scatteringimageswascarriedoutusingaShimadzuEPMA-1720Serieselectronprobemicro-analyzer,supplementedbyaquantitativespectrumanalysisthatdeterminedthemineraltypes.
简介:放大碎片长度多型性(AFLP)技术被用来在马尼拉蚌(Ruditapesphilippinarum)的四张自然人口分析基因差异,在中国的四个海区域分布式,我。e.,Bohai海,Huanghai海,华东海和华南海。264AFLPloci在195individuals被分析并且揭示了基因差异的高水平。多态的loci的百分比从92.13%~96.06%并且香农“s信息索引从0.2568~0.2756。由分析分子的变化(AMOVA),有在Qingdao和另外的三个海区域的人口之间的基因区别的高水平,这被发现。由Nei的聚合分析“spairwisedistances由地理起源组织了标本,除了Qingdao的人口。一个结论能被得出在在中国和一些不同差别的马尼拉蚌的四张自然人口有高基因的差异,这存在在之中并且在四张人口之间。结果也显示人的耕作活动将在Qingdao的人口的基因结构上有大影响。
简介:TheNandan-Hechimetallogeneticbeltisthemostimportanttin-polymetallicproducingdistrictinChina,andisthelocationoftheDachangsuper-largetindeposit.Basedonthedetailedfieldinvestigationandisotopicdata,thestagesofmagmaticactivityintheNandan-Hechimetallogeneticbelthavebeenlinedoutinthispaper.Throughthestudyaboutthegeochemicalcharacteristicsofdifferentgranites,andbyusingω(Al2O3)-ω(SiO2),ω(TFeO)/[ω(TFeO)+ω(MgO)]-ω(SiO2),AFM,ACFandRb-Yb+Ta,Rb-Y+Nb,Ta-Yb,Nb-Ydiscriminationdiagramsincombinationwithregionalgeologicalsettinganalysis,theauthorscarriedoutanalysesaboutthestructuralenvironmentfortheformationofthegranites,anddiscussedthestructuralenvironmentanddynamicsettingforthelargescalemineralizationinthisarea.OurstudyindicatesthatthemajorityofthegranitesinNandan-HechimetallogeneticbeltbelongtothePOGtype,whilethelaterstagealaskitebelongstotheRRG+CEUGtype.Thegraniteswereformedatthestageofstructuraltransformationfrompostorogenicphasetointraplatesetting.Butthemajorstructuralenvironmentischaracterizedbysteadyregionalextension.Theformationageforthegranitescoincideswiththetimeforthistransformation,andthistranslationenvironmentisfavoredforlarge-scalemetallogenesis.
简介:Inapreliminaryinvestigation,RandomAmplifiedPolymorphicDNA(RAPD)analysisandpartialmitochondrialND2genesequencingwereconductedtostudythegeneticvariationoftheIndianmackerel,Rastrelligerkanagurtaalonga450kmstretchofitsdistributiononthewestcoastofPeninsularMalaysia.Atotalof53individualsfrom6populationswereanalyzedusing4RAPDprimersandasub-sampleof15individualswaschosenforsequencingofpartialND2gene.Comparisonbetweenthe2markersrevealedgeneticstructuringintheRAPDresultsbutgenetichomogeneityforND2gene.Basedontheformertheremaybeatleast2geneticallydifferentiatedgroupsofRastrelligerkanagurtaalongthisstretch.
简介:Primitivemantle-normalizedPlatinum-groupelements(PGE)concentrationpatternsfortheZhengziyanwointrusionandDashibaoFormationbasaltsareofpositiveslope,similartomostoftheworld-classmagmaticNi-Cu-PGEsulfidedeposits.CharactersofthisintrusionanditsrelatedoresandDashibaoFormationbasaltsaretheirnegativePt-anomalyandhighconcentrationofRhrelativetoPtandPd,factsbeinginterpretedtobetheresultsofcrystallizationandfractionationofPt-alloysandspinelphase-freecrystallizationhistoryforthemagma,respectively.PGEparametersoftheDashibaoFormationbasaltsareconsistentwiththegeneraltrendofthosefoundfortheZhengziyanwointrusion,andthismightinferageneticlinkbetweenthem.
简介:Post-collisionalvolcanicrocksofMesozoicageoccurintheregionsadjacenttoGerze,partofthesouthernQiangtangTerraneofnorthernTibet,China.Geochronological,geochemical,andwholerockSr-Ndisotopicanalyseswereperformedonthevolcanicrockstobettercharacterizetheiremplacementageandmodelsfortheirorigin.Laserablation-inductivelycoupledplasma-massspectrometry(LA-ICP-MS)U-Pbzirconanalysesyieldedconsistentagesrangingfrom123.1±0.94Mato124.5±0.89Maforsixvolcanicrocksfromthestudyarea.Theintermediatevolcanicrocksbelongtothealkalineandsub-alkalinemagmaseriesintermsofK2O+Na2Ocontents(5.9%–9.0%),andtotheshoshoniticandcalc-alkalineseriesonthebasisoftheirhighK2Ocontents(1.4%–3.3%).TheGerzevolcanicrocksarecharacterizedbytheenrichmentoflightrareearthelements[(La/Yb)N=34.9–49.5]andlarge–ionlithophileelements(e.g.,Rb,Ba,Th,U,K,Pb,andSr),slightlynegativeEuanomalies(Eu/Eu*=0.19–0.24),andnegativeanomaliesinhighfieldstrengthelements(e.g.,Nb,Ta,HfandTi),relativetoprimitivemantle.Thesamplesshowslightlyelevated(87Sr/86Sr)ivaluesthatrangefrom0.7049to0.7057,andlowεNd(t)valuesfrom-0.89to-2.89.Theseresultssuggestthatthevolcanicrocksstudiedderivedfromacompositionallyheterogeneousmantlesourceandthattheirparentmagmaswerebasaltic.Themoremafic,parentalmagmastotheGerzevolcanicrockslikelyunderwentfractionalcrystallizationofclinopyroxene,hornblende,biotite,andpotassiumfeldspar,duringascent,withlittletonocrustalcontamination,priortotheireruption/emplacement.Whilethesevolcanicrocksexhibitgeochemicalsignaturestypicalofmagmasformedinadestructiveplate-marginsetting,itisplausiblethattheirmantlesourcemightalsohaveacquiredsuchcharacteristicsinanearlierepisodeofsubduction.