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简介：揭示发生到在Bangong-Nujiang缝术地区之中被抓紧的Nyainrongmicrocontinent的侏罗记tectonothermal事件，标明日期的40Ar/39Ar在microcontinent在地下室orthogneiss和侏罗记granitc片麻岩上被执行。在加热阶段，四件样品展出了扁平的高原年龄，与Tp在166176妈的范围集中了的价值；isochron年龄Ti在165175妈的范围被集中，并且他们的相应年龄是在许可的范围以内一致。年龄应该Amdo片麻岩和在侏罗记的magmatic岩石的冷却炮兵阵地的最后的变丑的时代是代表性的。geochronological研究证明了microcontinent的最后的变丑水晶的地下室并且冷却中生代大规模tectonothermal事件发生在晚中间的侏罗记。在中间的侏罗记，Nyainrongmicrocontinent经历了强壮的构造运动。为microcontinent与同位素地球化学与geochronological结合，tectonothermal事件的原因应该被归因于在Nyainrongmicrocontinent和南方卡恩格唐·布洛克追随者之间的碰撞向北方Bangong-Nujiang的subduction海洋的外壳。

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简介：陕西驾鹿金矿床首次发现的40种含氧金矿物,呈褐、紫、黑等不同色调,多为不规则粒状及微细晶集合体,粒径0.01~0.5mm;条痕紫、黑色、半金属光泽,不透明;反射多色性显著;摩氏硬度2~3.这40种含氧金矿物主体与黄铁矿、碲金矿和石英共生,属于内生热液成因.依据金的地球化学行为,以及区内含氧金矿物富含Te（10%~20%）和不等量Mn的特征,认为该矿床成矿元素（Au）主要是在碲酸及硫酸溶液中,在有氧化剂MnO2存在的条件下迁移富集成矿.通过细致的电子探针分析,初步确定了驾鹿金矿床中16个类型40种含氧金矿物,主要成分为Au、Pb、Fe、Te和O.这些矿物在主要成分上虽与前苏联发现的别斯麦特矿、毕利宾矿、博格丹诺夫矿以及我国东坪金矿床发现的金的碲酸盐矿物有类似之处,但因其普遍含不等的Mn、Ca或Al、As、Co、Ni等而又有所不同,因此很可能是一系列新的矿物种或新（亚）种金矿物.X-射线衍射分析表明,大部分晶体结构可能是由Au、Ag、Cu、Fe或Pb等金属互化物组成的假立方晶格与一个由β-TeO2（可能包括PbO或CaO）组成的斜方晶格的混晶,但不排除它们是含金氧化物的可能性.还有些可能是玻璃质或纳米级矿物,少部分则呈现准晶态物质的特征.

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简介：40Ar-39ArdatingofalbitefromtheMeishanandTaocunirondepositsyieldsplateauagesof122.90±0.16Maand124.89±0.30Ma,andisochronagesof122.60±0.16Maand124.90±0.29Ma,respectively.PhlogopitefromtheZhongshan-Gushanorefieldhasaplateauageof126.7±0.17Maandanisochronageof127.21±1.63Ma.Analysisofregionalgeodynamicevolutionofthemiddle-lowerYangtzeRiverregionsuggeststhattheporphyryirondepositswereformedasaresultoflarge-scalelithospheredelaminationandstrongsinistralstrike-slipmovementoftheTanchengLujiangfaultzone.Thecopper,molybdenumandgolddepositsysteminthemiddle-lowerYangtzeRiverregionwasformedduringthestresstransitionperiodoftheeasternChinacontinent.

简介：Byusingthe40Ar-39ArchronologicalmethodtodateK-feldsparfromK-feldspargraniteintheQiaohuotecopperdistrict,theauthorsobtainedaplateauageof274.78±0.44Maandanisochronageof272.7±3.0Ma.BecausethereisnotectonicdeformationoverprintedorhydrothermalalterationintheK-feldspargraniteintrusionafteritsemplacement,the40Ar-39AragerepresentsthecrystallizationageofK-feldsparinK-feldspargranite,i.e.thelatecrystallizationageoftheK-feldspargraniteintrusion,whichindicatesthattheK-feldspargraniteformedintheintraplateextensionalstageduringtheEarlyPermian.Moreover,basedonthespatialrelationshipbetweentheK-feldspargraniteintrusionandcopperorebodies,variationsofcopperoregrade,REEcharacteristicsofK-feldspargraniteandcopperores,andHandOisotopiccompositionsoffluidinclusionsincopperores,themetallogenesisoftheQiaohuotecopperdepositisdirectlyrelatedtointrusiveactivitiesoftheK-feldspargranite,andthusthecrystallizationageofK-feldsparinthegraniteapproximatelyapproachesthemetallogenicepochoftheQiaohuotecopperdeposit.

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.

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