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  • 简介:经过近一年的协商,我会所属22个专业委员会和两个工作委员会相继开展了换届组建工作。目前除微束分析测试专业委员会和宝石矿物学专业委员会外(名单另行公布),其余已完成换届组建工作,经秘书长审核,现将名单公告如下。

  • 标签: 专业委员会 中国矿物 地球化学学会
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  • 简介:近几十年来,国内外泥炭沼泽地球化学研究取得了一系列重要进展,特别是在脂类化合物和稳定同位素等方面.泥炭沼泽是一个良好的地质档案,泥炭纤维素碳、氢和氧同位素组成和比值是环境变化的综合参数,沉积脂类化合物含有反映有机质母源先质的骨架结构,这些标志物高分辨率地记录了全新世以来古气候、古植被和古环境的演变信息,在当今全球变化研究中占有相当重要的地位.本文综述了泥炭沼泽地球化学研究进展,侧重于泥炭沼泽脂类化合物和稳定同位素等标志物的地球化学研究现状和发展趋势;侧重论述了研究技术的发展、定性说明到定量分析的过渡、研究精度的提高及存在的问题,分析了这些分子标志物与植被演替、气候变迁和环境变化间的对应关系,指出了我国在该方面的薄弱之处以及需加强的领域.

  • 标签: 泥炭沼泽 脂类化合物 稳定同位素 古气候 古植被 古环境
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  • 简介:生物成因煤层气一般可分为原生和次生生物成因,它们在生成机理上有许多相似之处,但也有所不同,导致后期保存和同位素组成上的差异.研究指出,原生生物成因气不能被大量保留在煤层中,气田中的生物成因气多为次生生物成因气;次生生物成因煤层气分布比较普遍,含量较为丰富,且生物成因煤层气埋藏深度浅,勘探成本低,因此次生生物成因煤层气具有不容忽视的巨大资源潜力.

  • 标签: 煤层气 原生生物成因 次生生物成因 生成机理
  • 简介:在分析四川稻城地区地热资源形成的地质背景的基础上,初步研究了该区地热资源分布特点和温泉水的同位素地球化学特征.结果表明,稻城县地热水的径流和排泄受构造作用的控制,断裂、断层地带地下径流多,是形成温泉的主要地区.在深大断裂发育处或断裂交汇地带,温泉往往成群出露.温泉水的同位素组成具明显的季节性效应;与大气降水季节性效应相反:夏季温泉水相对富轻同位素,冬季则明显富重同位素;反映其夏季主要受δD、δ18O值低的高山常年积雪溶融水补给,冬季主要为δD、δ18O值高的地下水补给.

  • 标签: 四川 地热资源 分布 温泉水 同位素 地球化学
  • 简介:本文研究了四川绵竹三箭水及其邻区水体的同位素组成特征,以氘过量参数(d=δD-8δ18O)在地热勘探中的示踪作用,再通过对研究区地下水氘过量参数和水体氚含量(T)的相关性分析,综合运用于查明区内温泉地下水的成因,包括地下热储层内地下水的来源、补给源区、运移途径等等;确定水体均来源于大气降水,山前盆地深部地下水的补给源区在西、西北部高山区,径流方向由西北向东南,径流途径和在地下滞留时间都很长,并由此圈定了几个地热勘查的重点靶区.

  • 标签: 水体同位素 氚过量参数 地热勘探 地质条件 地热水
  • 简介:水热爆炸是活动性地热田的典型显示.腾冲热海火山地热区历史上曾发生过强烈的水热爆炸活动,但前期一度沉寂.1993年以来水热爆炸活动再度活跃.在过去十年间,研究区内发生过较大的爆炸喷发事件20余次,且规模越来越大.本文根据对爆炸形成泉点的逸出气体化学和氦同位素组成的测试结果,研究了区内近期水热爆炸活动的演化特征.逸出气体化学和氦同位素组成特征指示,区内近期引发水热爆炸活动的气体源区有从浅层、中层向深层发展的趋势;作者认为,区内未来可能发生更大规模的爆炸活动,其危险性应引起高度关注.

  • 标签: 腾冲热海火山地热区 水热爆炸 阶段性演化 危险性
  • 简介:摘要:在模拟的酸性土壤条件下,利用制备的低聚合羟基铁蒙脱石复合体对铬酸根进行吸附实验。重点研究了吸附条件对复合体铬吸附能力的影响,对比了蒙脱石和含水氧化铁。结果表明,实验条件下复合体有较强的铬吸附能力,其铬吸附量低于铁沉积物而明显高于蒙脱石。铬初始质量浓度是影响复合体铬吸附量的最主要因素,离子强度次之。吸附时间(12h以上)、温度、pH值对复合体铬吸附量的影响很小;说明在酸性土壤条件下,复合体有强且稳定的铬吸附能力。

  • 标签: 羟基铁离子 蒙脱石 复合体 铬酸根 吸附 温度
  • 简介:Tourmalineiswidespreadinthehoststrataofstrata-boundbasemetalsulphidedepositsintheDevonianmetallogenicdeistrictaroundShanyang-ZhashuiineasternQinling,Asamemberoftheschorl-draviteseries,thetourmalineischaracterizedbyMg>FeandNa>Ca,showingapparentchemicalzonationwhichrecordsthegeochemistryduringitsformationandsubsequentregionalmetamorphismandhydrothermaloverprint.Theclosesimilarityinchemicalandisotopicconstitutionsbetweenthetourmalineofthemainmetallogenicepochinthisdistrict[FeO/(FeO_MgO)=0.34-0.39andδ^11B=-7.6‰--8.8‰]andthoserelatedtomassivesulphidedepositstypicalofsubmarine(exhalative)hydrothermalsedimentation

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  • 简介:TheYushugouterrainofhigh-pressuregranulitefaciesinsouthernTianshanMountainiscomposedmainlyofanophiolitesuite.Mostselectedziroconsareroundorellipticalinshape,andsomeareoftetragonalprismwithroundedges.Thegranulometricanalysesshowthattheyarewellsortedinsedimentation.ZrO2/HfO2ratiosinzirconsrangefrom45to57.thesecharacters,togetherwiththepetrologicandgeochemicalcharactersofplagioclase-garnet-orthopyroxenitebearingzircons,indicatethattheprotolithofplagioclase-garnet-orthopyroxenitemaybederivedmainlyfromvolcanicbasesurgesedimentarydebrisinoceanicislandsandfromclaysformedbyseafloorweathering.Zirconsaresimplyofpyroclasticdebris.Theophioliteformationageof(440±18)Maandthefirst-stagemetamorphicage(amphiboliteorgranulitefacies)of(364±5)Mawereobtainedwithamethodofmultiplegrainsindifferentgroupsandamethodofconcordiaplot.TheseagesprovideimportantinformationonthetemporalandspatialoccurrenceofsouthernPaleoxoicTianshanOcean,Thesubductionrateoftheoceaniccrustandtheformationmechanismofophioliteofgranulitefacies.

  • 标签: 锆石 铀铅同位素年龄 麻粒岩 天山地区 新疆 地形
  • 简介:Phlogopite-amphibole-pyroxenitexenolithscontainedinthealkalibasic-ultrabasicsubvolcaniccomplexinLangao,shaanxiProvinece,arecomposedofdiopside,Ti-richpargasite,phlogopiteapatite,spheneandilmenite,whichhavesubsolidusmetamorphism-deformationtexturessuchastriple-points,cataclasticboundariesandkink-bands,MineralChemicalcharacteristicsshowthatthediopside,Ti-richPargasiteandphlogopitearederivedfromthemantleandaretheprioductsofmantlemetasomatism,Comparedwithnormalmantle-derivedspinel-lherzolites,thexenolithsareenrichedinTiO2,Fe2O3,CaO,Na2OandK2O,withapparentdepletioninMgO,Chondrite-normalizedREEpatternsandprimordial-mantlenormalizedtraceelementsdatashowthattheyareenrichedinREE(EspeciallyLREE)andincompatibletraceelements,Thepetropraphic,mineralogicalandpetrochemicalcharacteristicsindicatethatthexenolithsaremetasomatizedmantlexenoliths,whichofferstheevidenceformantlemetasomatismandrepresentstheanomalousmantlebeneaththeEarlyPaleozoicriftinnorthernDabaMountains,Theagentsofmantlemetasomatismareprobablyderivedfromtherisingofmantlehotplumes,Thepriocessesofmetasomatismvariedfromlimited-rangefluidmetasomatismindeepmantle(>90km)topervasivemetasomatismofsilicatemelt.

  • 标签: 金云母 闪石 辉岩 包体 表生交代变质作用 陕西
  • 简介:ExperimentshavebeenperformedonthesystemMgO-SiO2-Cr-Oat0-2.88GPaand1100-1450℃,focusingonthestabilityofCr^2+inolivine(O1),orthopyroxene(Opx)andspinel(Sp)anditspartitioningbetweenthesephases.Analyticalreagentgradechemicals,MgO,SiO2,Cr2O3.andCrwereusedtomakestartingmixtures.ExcessCr(50%)wasthenaddedinthesemixturestoensurethattheresultantphaseswereinequilibriumwiththemetalCr.FluxofBaO+B2O3(%)wasaddedforfacilitatingexperimentalequilibriumandcrystalgrowth.Crwasusedascapsulematerial.AllphasesintheproductwereidentifiedbyX-rayandanalyzedbyelectronmicroprobe,ThecontentsofCrOinthedifferentphases(O1,OpxandSp)werecalculatedaccordingtostoichiometry.TheobtainedresultsofcalculationindicatethatCr^3+inOlandOpxisnegligible.Theexperimentalresultsshow;(a)withincreasingtemperatureanddecreasingpressure,Cr^2+solubilityinOl,OpxandSpincreases;(b)withincreasingtemperature,thepartitioningcoefficientofMgandCr^2+betweenOlandOpxdecreases,thatbetweenOpxandSpincreases,andthatbetweenOlandSpremainsalmostunchanged;(c)theeffectofpressureonallpartitioningcoefficientsisnegligible.

  • 标签: 铬离子 可溶性 橄榄石 尖晶石 化学反应
  • 简介:UltrabasicrocksintheMianxian-LueyangophioliticmelangezoneincludeharzburgiteanddunitewhichexhibitLREEdepletionwithremarkablepositiveEuanomaly.ThediabasedikeswarmshowsLREEenrichmentbutslightlynegativeEuanomaly.MetamorphosedvolcanicrockscanbedividedintotwogroupsintermsoftheirREEgeochemistryandtraceelementratiosofTi/V,Th/Ta,Th/YbandTa/Yb.OneisthsMORB-typebasaltwithLREEdepletion,representingthefragmentsofoceaniccrustandimplyinganassociationoftheMORB-typeophioliteandanancientoceanbasinbetweentheQinlingandYangtzeplatesduringtheMiddlePaleozoic-EarlyMesozoicera.Theotercomprisestheisland-arcvolcanicrocksincludingtholeiiticbasaltandalargeamountofcalc-alkalineintermediate-acicvolcanicrock,whichcouldnotbethecomponentoftheancientoceaniccrustbuttheresultofmagmatismatthecontinentalmargin.ThisindicatesthattheMianxian-Lueyanglimitedoceanbasinhadundergoneawholeprocessofdevelopment,evolutionandvanishingfromDevonian-CretaceoustoPermian.AndtheQinlingareahadbeconeanindependentlithosphericmicroplate,onthesouthernsideofwhichtherewereexhibitedthetectoniccharacteristicsofactivecontinentalmarginsduringtheLatePaleozoic-EarlyMesozoic.Thatistosay.theQinlingcannotbesimplyconsideredasaresultofcollisionbetweentheYangtzeandNorthChinaplates.

  • 标签: 地球化学 蛇绿岩 秦岭地区 火山岩 稀土元素 缝合带
  • 简介:Basedondetailedgeologicstudy,theimportantroleofstructuringintheformationofgolddepositsintheareaisdiscussedwithspecialreferencetostructuralevolution,Syngeneticfaultingcontemporaneouswithtectonic-volcaniceventsisthoughttoberesponsibleforprovidingtheore-formingmaterialatdepth.ThelithofaciesformedbyhighlyalternatingdepositionofterrestrialandcarbonatedetritusischemicallycharacterizedbytheassemblageofAu-Sb-As,constituteingafavorablesourcebedfortheactivationandenrichmentofgold.Thisgoldsourcebedhasundergonefourmajorstagesofstructuraldeformation,accompaniedbymulti-stagedalterationandmineralization.

  • 标签: 金矿床 陕西 延展性 脆性 地质构造 成矿作用
  • 简介:BasedonelectronprobeanalysesofthemineralsandbulkcompositionoftheCenozoicvolcanicrocksfromYumenandHohXillithodistricts,Qinghai-Xizangplateau,theformingconditionsincludingthetemperatureandpressureofthoserocksarestudiedinthispaperAccordingtothethermodynamiccalculationresultsofmineral-meltequilibrium,thedepthoftheasthenospheresuperface(about75-130km)forthenorthernpartoftheQinghai-XizangplateauduringtheCenozoicissuggested.Finally,thispaperindicatesthattheCenozoicvolcanicrocksinthenorthernpartoftheQinghai-Xizangplateaumainlyconsistofshoshoniteseries.Theirformingtemperatureis630-1039℃andformingpressureisbetween2.3-4.0GPa.Therockswereformedintheintracontinentalorogenicbelt,ofwhichtheprimarymagmawasoriginatedfromaparticularenrichmentuppermantleandaccretedcrust-mantlebeltofdirectlyfromasthenosphericsuperfaceasaresultofpartialofpyrolite.

  • 标签: 新生代 火山岩 青海 西藏 岩石成因
  • 简介:Wateristhemostactivecomponentinallgeologicalsystems.Ithasanimportanteffectonthephysicalpropertiesofmineralsandmelts.ItalsoplaysakeyroleintheevolutionoftheEarth.Accuratethermodynamicsdataonwaterarecurrentlyconfinedtopressuresbelow1.0GPaandtemperaturesbelow900℃.PresentedinthispaperarenewdataavailableontheP-Tpropertiesofwateratpressuresupto5.0GPa,develogedfromdifferentialthermalanalysisandultrasonicwaveamplitudeanalysis.Ithasbeenfoundthattheremayexistanotherternarypointat3.0GPaandthatultrasonicwaveamplitudechangeofice-watertransitionshowstwoinflectionpointsabove2.0GPa,consistentwiththetwopeaksofdifferentialthermalcurvesabove2.0GPa.Itmaybeanewphenomenonwhichneedsfurtherstudy.

  • 标签: 高压作用 冰水平衡 超声波分析 高温 地球体系 P-T轨迹
  • 简介:Thesediment-hosteddisseminatedgolddepositsintheOinlingregionareofsedimentation-slight-metamorphicoriginsuperimposedbyhydrothermalreworkingatmoderate-lowtemperaturesandarewellcomparablewiththetypicalCarlingolddepositsintheUnitedStates.Inviewoftheconfusingconceptconcerningthe“sediment-hosted”and“Carlin-type”golddeposits,theauthorsproposethattheterm“sediment-hostedgolddeposit”shouldbeusedinabroadsensewhichencompassesatleastthefoursubtypes,i.e.,theCarlintype,themetamorphicfineclastictype,thehydrothermalsedimentarytypeandtheveintype.Inoterwords,the“Carlin-type”shouldnotbeusedasasynonymfor“sediment-hosted”butisrecommendedasasubtypeunderthegeneralcategoryof“sediment-hostedgolddeposits”

  • 标签: 金矿床 秦岭地区 沉积物 矿化作用 成因