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简介：ThedifferentialenrichmentofgoldandarsenicobservedinAs-bearinghydrothermalgolddepositsinSouthwestGizhouisinducedbyvapor-liquidseparationinresponsetochangingphysico-chemicalconditionsduringthehydrothermalevolutionandisareflectionofthegeochemicalbehaviorofthetwoelements.

简介：TherearetwomaintypesofirondepositsintheMiddle-LowerYangtzeValleydistrict.Bothofthemunderwentpost-magmatichydrothermalprocessesduringoreformation.Ironinthehydrothermalorebodieswasderivedlargelythroughmobilizationfromsubstantiallyconsolidateddiroiticintrusives.Wall-rochalterationzonationindicatesthatiron-mobilizinghydrothermalfluidsevolvedinatrendofdecreasingalkalinity,whichissuggestedbyregularlydistributedwall-rockalterationsformedbyiron-mobilizinghydrothermalfluidsandisincontradictionwiththecurrentchloride,chloridecomplexandbicarbonatemodelsforironmobilization.ThecloseassociationofcarbonatizationwithironoresandthehighconcentrationsofreducedgasessuchasCO,CH4andH2influidinclusionssuggestthatironismostprobablytransportedintheformofironcarbonylsduringpost-magmatichydrothermalprocesses.Inthelightoftheironcarbonylmobilizationmodel,explanationsaremadeoftheconstraintsonoresofsomegeologicfactorssuchasmelanocraticalteration,carbonatization,carbonatestrata,structuralfractures,cyptoexplosivepipesandembryoores.

简介：沉积物被发现了沿着长江的中间降低的活动范围在这个区域散布的沉积hydrothermal-diplogenetic铜的系列，和theirmetallogenetic机制仍然在热争论。以便揭示沉积过程和热水的重迭的形成矿石的动力学，并且在铜的丰富和降水评估沉积黄铁矿的角色，在黄铁矿和CuCl_2答案之间的反应的一套模仿的实验被进行。根据Dongguashan铜沉积物的形成theore液体的物理化学的特征，安徽省，当试验性的压力，和试验性的温度分别地被放在450，350，250和150℃，100MPa被选择。在与0.2mol/LCuCl_2和1.0mol/LNaCl从Shimenkou阶层界限黄铁矿沉积物和答案孤立的黄铁矿谷物之间的反应试验性地被模仿。然后，在表面地形学的变化和试验性的黄铁矿谷物的表面化学被记录使用的扫描电子显微镜学(SEM)，原子力量显微镜学(AFM)，钻electronspectrometry(AES)和X光检查光电子光谱学(XPS)，并且答案和最新形成的矿物质用电感耦合等离子体(ICP-AES)和X光检查衍射(XRD)被分析技术。黄铁矿表面的Desulphurization被观察，新铜矿物质被检测。黄铁矿能在试验性的条件下面从答案为铜的丰富和降水充当一个geochemical障碍，这被建议。而且，沉积hydrothermal-diplogenetic铜沉积物的形成矿石的机制被讨论。

简介：TheUpperSinianbeddedchertsarewidelydistributedonthesoutheastcontinentalmarginoftheYangtzeplate,withatotalthicknessrangingfrom20to150m,Thechertsareverysimpleinchemicalcomposition,withthecontentsofsiliceousmineralsexceeding90%andthoseofothermineralspeciesbeingverylow.Thetotalcontentoftraceelementsisconsiderablyvarialbe,Thecontentsofmosttraceelementsarelowascomparedwiththeircrustclarkevalues.ButthesechertsareveryrichinthetraceelementsBa,As,Ab,AgandU,coupledwithrelativelyhighcontentsofFe,MnandlowcontentsofAl,Ti,andMg,ItcanbeidentifiedasthechertsofhydrothermaloriginintermsofthevaluesofFe/Ti,(Fe+Mn)/Ti,Al/(Al+Fe+Mn)andU/Th,IntheAl-Fe-Mn,andFe-Mn-(Cu+Ni+Co)×10diagramsandlg[U]-lg[Th],Cr-Zrdiagrams.allthesamplesfromtheareastudiedfallwithinthehydrothermalsedimentfield.Allthesecharacteristicsshowthatthechertsaremainlytheproductofhydrothermalprocesses.Thefactthattheδ30Sivaluesofthechertrangefrom0.0‰to0.7‰withδ18Ofrom20.1‰to23.6‰cleralymanifeststhatthesubmarinehydrothermalwateristhemainsourceofsilica.

简介：Thispaperpresentsamethodofestablishingahydrothermalore-formingreactionsystem.Onthebasisofthestudyoffourtypicalhydrothermaldeposits,thefollowingconclusionsconcerninggeochemicaldynamiccontrollingduringhydrothermalmineralizationhavebeensionsconcerninggeochemicaldynaamiccontrollingduringhydrothermalmineralizationhavebeendrawn:(1)Theregionaltectonicactivitiescontroltheconcentrationanddispersionofelementsintheore-formingprocessintermsoftheireffectsonthethermodynamicnatureandconditionsoftheore-formingreactionsystem.(2)Duringhydrothermalmineralizationtheactivitesofore-bearingfaultscanbedividebintotwostages:thebrittlesplittingstageandthebrittle-toughtensingstage,whichwouldcreatecharacteristicallydifferentgeodynamicconditionsforthegeochemicalthermodynamicore-formingsystem.(3)Thehydrothermalore-formingreaactionsystemisanopendynamicsystem.Atthebrittlesplittingstagethesystemwassostronglysupersaturatedandunequilibratedastospeedupandenhancethecrystallizationanddifferentiationofore-formingfluids.Andatthebrittle-toughtensingstage,theore-formingsystemwasinaweaksupersaturatedstate;withdecreasingtemperatureandpressurethecrystallizationoforeformingmaterialwouldshowdown,anditcanberegardedasanequilibratedstate.(4)Inthelatesstagesofhydrothermalevolution,goldwouldbeconcentratedintheresidualore-formingsolution.Thepulsatingfractureactiviteinthisstageledtothecrushofpyriteoreanditwasthenfilledwithgold-enrichedsolution,forminghigh-grage“fissure”goldore.Thisore-formingprocesscouldbecalledthecouplingmechanismoforeformation.

简介：REEmobilityduringhydrothermalore-formingprocesseshasbeenextensivelyinvesti-gatedinrecentyearsandthepotentialofREEtoprovideinformationaboutoreformingprocesseshascommonlybeenrecognized.TheDongpinggolddeposit,whichislocatedinnorthwesternHebeiProvince,China,occurringintheinnercontactzoneoftheShuiquangousyenitecomplex,isspatially,andprobablygenetically,relatedtothesyenite.Thedepositwasformedunderthemoderatetohightemperature(220℃to320℃),weaklyacidictoweaklyalkaline,ratherhighfo2(lgfo2=-30～-34)environment.TheREEstudyofthehostrocks,alteredwallrocks,oresandganguemineralsfromthedepositsuggeststhattheREEshavebeenmobilizedanddifferentiatedduringK-feldspathizationandsilicification.TheextremelyalteredsyeniteenvelopingauriferousquartzveinshowspositiveCeanomalyandlargerLREE/HREEratiothanthatoftheunalteredsyenite.TheREEconcentrationsandpatternsoftheoresaredeterminedbytheoretypesandmineralassemblages.LREE/HREEratiosintheganguequartzandhydrothermalK-feldsparsarerelativelylow.Themostsignificantobservationisthattheganguequartzshowssig-nificantpositiveEuanomaly,whereasthehydrothermalK-feldsparsshowlesssignificantornopositiveEuanomalyatallrelativetotheprimaryfeldsparintheunalteredsyenite.ItisevidentthattheREEsaremobileduringK-feldspathizationandsilicificationintheoreformingprocess.WeaktomoderateK-feldspathizationcausedREEmobilitywithoutapparentdifferentiationwiththeexceptionofextremeK-feldspathizationandsilicificationwhichresultedinsignificantdepletionofHREEandEuandrelativeenrichmentofCe.TheREE,Y,U,ThandAucontentsofthesyenitedecreaseasthedegreesofK-feldspathizationandsilicificationoftherocksincreasetowardstheauriferousquartzveins.Astheoresweredepositedunderaratheroxidizedenvironment,Ce4+predominatedoverCe3+.Theprecipitationoftheformerinthefor

简介：在这糊REE集中和Sr和从Furong矿石的Bailashui锡矿床的荧石的Nd同位素组成回答的在场的作者，南部的湖南省。结果证明在荧石的REE的全部的数量通常是低的，从有在学习区域的Qitianling花岗石的类似于那些的使球粒状陨石正常化的REE分发模式的0.705～8.785μg/g，与显著否定Eu异例由LREE丰富模式描绘了。荧石在范围以内在Sr同位素组成变化0.70830.7091，价值比在这个区域的主人碳酸盐岩石的那些是比花岗石并且高的那些低的。ɛ荧石的Nd(t)价值在−9.4和+10.3之间变化，两个都揭示那外壳--并且披风来源材料涉及形成矿石的热水的液体。在这张矿床上与以前的研究结合了，Bailashui锡矿床是速度集合并且仔细空间地在这个区域与花岗石的岩浆酌联系。热水的荧石是在热水的液体和海洋的碳酸盐摇的花岗石的magmatic之间的液体/岩石相互作用的产品。而在形成矿石的液体的Sr主要来自热水的液体和海洋的碳酸盐摇的花岗石的magmatic，在形成矿石的液体的REE和F从花岗石被导出，尽管在Sr同位素组成的变化不能被这二结束成员的简单混合物解释。证据证明形成矿石的液体具有外壳披风的混合起源，但是液体可能是，这不完全地一致，这可以被不同来源的液体的不同类的混合引起。