金矿床中英文对照外文翻译文献

PAGE9外文翻译PAGE1中英文对照外文翻译文献(文档含英文原文和中文翻译)含金剪切带型金矿床研究进展摘要：韧性剪切带是热液活动的有利场所，对于金成矿具有重要意义。本文对含金韧性剪切带与金成矿的关系进行了总结，并对剪切带活动的阶段性对成矿的控制作用、金矿化产生的机制和剪切带型金矿床的成矿模式进行了探讨。关键词：含金剪切带；金矿床；研究进展1剪切带与金矿化的关系世界上许多脉金矿床，多与大型线性断裂带有关，这些断裂带主要是剪切带型或强烈片理化带，是含金热液上升的通道和富集的场所。由于韧性剪切带常具有延伸较远较深、长期活动的特点，又是岩浆活动及热液活动比较强烈的地带，对成矿作用十分有利。国内外学者都十分重视剪切带与成矿作用关系的研究，其中对金矿的研究尤为深入(Col—vine，1989；Foster，1989；吴美德，1989；何绍勋等，1996)。剪切作用不仅使一些富含SiO：的岩石强烈破碎和糜棱岩化，同时形成多孔隙和晶洞的砂糖状石英，而且还使成矿物质重新调整产生新的矿物，并使分散的金属元素活化、迁移，在有利地段富集成矿。剪切带构造不仅是控矿因素，而且也是重要的成矿机制(吴美德等，1989)。含金剪切带型金矿是一类既包括一些脉型矿床，也包括一些浸染型矿床，以剪切作用为成矿机制和控制因素的金矿床。1980年Ramsay正式提出并系统地阐述了韧性剪切带以后，国内外已有很多学者对韧性剪切带形成机制作了补充的研究(如Lister等，1984)。Ramsay(1980)提出剪切带可分为脆性、脆一韧性和韧性剪切带三类。早在1977年Sibson研究英国OuterHebride逆断层的特点后，就提出了一个大型断层双层流变学模式。上构造层次是位于地壳上部，由摩擦机制产生随机组构的断层岩组成的。下构造层次是深部的韧性剪切带，由塑性机制产生的具有线理和面理组构组成的糜棱岩所组成的。以及二者过渡相，温度为250～350℃，韧脆性变形为主，相当于绿片岩相变质。之后，Mattauer(1980)、Scholz(1988)和朱志澄(1988)在该模式的基础上进行了补充和完善。韧性剪切带在变形过程中，产生大量宏观和微观构造，为金矿溶液提供了空间和通道。由于应变硬化和地壳由于造山运动而上升等原因在韧性带上迭加着脆性、脆韧性变形，例如迭加在剪切带上的Riedel断裂系统。这些系统都是很好的容矿构造。许多的脉状金矿就产生在这种断裂中。同时剪切带驱动成矿物质的迁移和集中(Colvine，1989；Foster，1989；)。流体存在于不同类型和不同性质的剪切带中。成分以CO2-H2O为主。在韧性剪切带中，变质流体，尤其是动力变质流体起着应变软化作用，往往形成中高温热液蚀变。在脆性剪切带中，系统处于一个开放系统，水岩作用十分明显，物质交换作用强烈，往往形成中低温热液蚀变。流体作用的结果，往往形成交代蚀变带、热水角砾岩带、热液脉带、微裂隙带和矿化带等。剪切带中流体往往携带有大量的成矿物质，而成为成矿流体。成矿流体具有复杂的来源，主要有：岩浆上侵过程中分解或结晶释放的流体，变质过程中脱水脱挥发份产生的流体，压实或构造收缩挤压产生的流体，大气降水或海水下渗循环产生的流体，地幔排气作用产生的流体以及交代作用产生的流体。2含金剪切带的演化阶段Bonnemaison等(1990)在研究法国海西期基底的含金剪切带时提出了三个演化阶段。他们的工作表明具有经济意义的矿床与剪切带相继发生的多阶段的复杂演化有关。每个阶段都有其自己的特点，并在自专属的矿物相内富集金。2.1早期阶段凡受到剪切变形作用，特别是韧性一半脆性变形作用改造的岩石，与围岩相比具有更大的渗透性。它们对流体起着通道的作用。变形作用和热液作用联合的结果导致了岩石中的矿物成分和地球化学成分发生重大变化。在这一阶段，含金剪切带绿泥石化和硅化极为发育。硅化的强度随变形的强度和重复的次数而增大。绿泥石化的同时，黑云母分离出来TiO：，形成了白钛石或金红石。这些矿物含量的多少反映了该阶段的热液作用的强度。在热液蚀变的同时，在片理面上伴有含金磁黄铁矿的结晶作用，其含金量通常不高。标志是含金磁黄铁矿矿物在糜棱岩化岩石内数量不大。Colvine(1989)和Foster(1989)认为该阶段主要发生于角闪岩相的变质作用条件下的，蚀变呈弥散性，通常不形成具有经济意义的矿床。在局部地区，变形作用由韧性演变到韧脆性的过渡阶段，也就是从角闪岩相转变到绿片岩相的条件下，热液蚀变达到相对较强时，使含金剪切带的早期阶段发育成熟。此时硅化作用十分发育。并形成了含矿构造的核心，含金磁黄铁矿转变为白铁矿和黄铁矿，并为含矿构造核心带来了一定数量的Fe、Cu、Zn、Sb等元素，尤其是元素As。作者认为，As元素发育程度通常是与基底岩石有关，例如在华熊地块中含金剪切带型金矿床内就很不发育，金矿床不含毒砂、硫砷铜矿等。2.2中期阶段含金剪切带中期阶段是与剪切带内或其边部的脉状构造出现为标志的。实际上，自早阶段起，剪切作用就导致了剪切带的局部张开或产生了一些扩容构造，这就使得含不同数量硫化物石英脉充填于其中。这类石英脉优先发育在富含二氧化硅的花岗岩、片麻岩和酸性火山沉积岩等岩层内。这些Si0的形成是通过剪切带内流动的热液使得容矿围岩发生了侧分泌现象。这些张性构造通常不含矿。当这些构造发生于剪切带内时，至多在这些构造的脉壁上见到早期阶段的矿化发生了轻微的活化。这些重新活化可在石英内或新结晶的硫化物内产生小颗粒金，如果这类活化作用不广，形不成具有经济意义的矿化。若含金剪切带继续发生新的活动，充填在老张性断裂带内的充填物会再次遭到破碎并优先矿化，是含金剪切带中期阶段的成熟标志。金矿化是由剪切带早期含金硫化物(含金磁黄铁矿或毒砂)不稳定和出现自然金的热液流体向扩容构造的转移而形成的。这是金矿形成的重要时段。与中期阶段的含金剪切带伴生的硫化物矿物共生组合，远比早期阶段复杂。在含金剪切带发育成熟期间，也进入了Sn、W、Bi、Mo等新的元素阶段。成熟期的的金矿化的金品位相对很高。在硫化物内，金并未显示出来与某种特定矿物有任何优先的伴生关系，它可于其中的多个矿物相伴生。中期阶段的矿化可使早期阶段的矿化全部覆盖掉，要区别二者相对较难。只有由原先的磁黄铁矿转变为白铁矿和黄铁矿时的叶片状和纤维状结构还能证明以前曾存在过磁黄铁矿。2.3晚期阶段在拉伸构造机制下，含金剪切带内发育了一系列张性构造，如张裂隙、网脉状等，从而引起矿物相产生了新的有意义的变化。矿物就会形成大量小晶洞，在这些小晶洞中，沙糖状石英重新结晶成为细粒的自形石英。这时金呈毫米级的颗粒产于石英颗粒之间或石英的晶洞内。硫化物矿物主要为含辉锑铅银矿、银黝铜矿、脆流锑银铅矿和方铅矿，以及大量的银金矿。该阶段以含银量增高为特征。此阶段虽然能采到特别富金的矿石样品，但矿化的经济意义有限。Bonnemaison等(1990)在此基础之上，把含金剪切带划分为早、中、晚三种类型。其中，具有经济意义的剪切带型金矿床主要与剪切带中晚期阶段密切相关。中晚期阶段使早期阶段初步富集的金进一步活化，转移到有利空间沉积成矿。中晚期的剪切带的形成温度，以及变形行为导致的扩容带是金矿床的形成有利阶段。划分早期与中期阶段的标志是磁黄铁矿被黄铁矿、白铁矿取代(高温到低温的转化)，糖粒状石英出现，以及大脉状和网脉状构造发育(韧性向脆韧性的转化)等。中晚期剪切带相当于通常意义的脆韧性阶段。关于韧性剪切带与金矿化的成因关系和类型划分上，我国一些学者在研究胶东半岛金矿时，曾提出了石英脉型和破碎蚀变岩型，分别以玲珑金矿和焦家金矿为代表。前者在上、后者在下的构造层次关系(姚凤良等，1990)。何绍勋等(1996)在研究韧性剪切带与金矿化的关系时，分为韧性剪切带型金矿和蚀变破碎带型金矿。韧性剪切带型的金矿是指由韧性剪切作用而形成的矿床，该矿床严格受韧性剪切带控制，并与韧性剪切带上具有空间和时间上有成因联系的金矿床，如广东河台金矿床(段嘉瑞等，1992；刘伟等，2006)。蚀变破碎带型金矿是指产在韧性剪切带系统内由后期热液蚀变成矿作用所形成的金矿床。该矿床仅与剪切带仅有空间关系，并无时间和成因上的联系。3剪切带型的金矿床的成矿模式由于该类矿床受剪切带控制，在不同的构造部位出现不同的矿石组构特征。Colvine(1989)和Foster(1989)分别对加拿大苏比利尔金矿省和津巴布韦老变质岩系中的产于剪切带金矿床进行了描述，并建立了剪切带中的金矿床模型。苏比利尔金矿省金矿床产于大规模的走滑和倾剪切带中。形成时代为晚太古代。金就位于剪切张性构造中。围岩为河流相一冲积相沉积岩、长质侵入岩以及碱性火山岩中。不同的变质相和不的变形条件下，金矿脉从单脉到群脉产出也不。在不同变质相围岩蚀变具有不同的特点，反映矿物组成是相对稳定的，变质作用未叠加其之。时间上反映为晚太古代剪切带和区域变质作用同时的。通过围岩变质作用的级别来确定矿化的深度。在角闪岩相变质作用下，磁黄铁矿是典型的蚀变硫化物，缺少石膏，或很少，以韧性变形为主。矿石组构呈叶片状。长英质岩石相对矿化较早。在绿片岩相下，岩石变形以脆性和韧脆性为特征，矿化以脉状和细脉状为特征，矿石成分主要为黄铁矿和石膏。浅部位变形时以脆性变形为主，矿石组构为角砾状或网脉状。蚀变基本呈对称分布。硅化主要位于构造带中，围岩中碳酸盐化较为普遍，邻近矿体，有硫化物矿化和钾化。蚀变带的宽度可达2km。蚀变类型主要取决于围岩岩石特征和温压条件。在富硅岩石中，钾化非常普遍；在镁铁质岩石中碳酸盐化和黄铁矿化较为普遍。对同种热液来说，硅酸盐蚀变。金在>400℃或450℃时溶解于热液中，沉淀一般发生在降温、减压或在扩容带内，低于300～450℃时发生沉淀，聚集成矿。一般情况下，低绿片岩相环境中，矿化表现为脉状和角砾状矿石。中高绿片岩相环境中，以韧脆性变形为主，矿化以脉状为主。低中角闪岩相，以韧性变形为主，有叶理状、条纹状矿化和极少量的微脉状矿化。在绿片岩相和角闪岩相边界处，矿化主要以脉、不规则脉、剪切叶理矿化为主。剪切变形特征受围岩的性质、应变速率及围岩压力的影响。围岩的性质不同，矿化结构也不同。在能干层中，以发生扩容带(易发生脆性)，主要以脉状矿石为特征。当流体压力大于围岩时，岩石易出现脆性变形，而出现了脉状矿石。这种脉状矿石是由于流体压力大而形成的裂隙不断重复的结果。围岩蚀变一般发生与断裂带附近几十公分的范围内。原文：AdvancesinductileshearzonesandtheirgoldmineralizationsignificanceABSTRACTDuctileshearzonesplayanimportantroleingoldmineralizationsincetheyarefavorablesitesforgeneratingandtransferringofgold—bearinghydrothermalfluids．Thispapersummarizestherelationshipsbetweenductileshearzonesandgoldmineralization．Differentmovementstagesofshearzonesandgolden—richmentmechanism，alterationcharacteristicsandthemetallogenicmodelarealsodiscussedinthispaper．Keywords：gold—bearingshearzone；golddeposit；researchadvance1.shearzoneandtherelationshipbetweengoldmineralizationManyveinsofgolddepositsintheworld,andmorerelevantwiththelargelinearfaultzone,whichismainlyfaultorshearzonewithstrongschistosity,istheincreaseinchannelsandhydrothermalgoldenrichmentsites.Asanextensionofductileshearzonesoftenhaveafardeeper,long-termactivities,features,andmagmaticactivityandhydrothermalactivityisrelativelystrongintheareaof​​mineralizationisveryfavorable.Scholarsattachgreatimportancetorelationsbetweenshearzonesandmineralizationstudy,whichisparticularlyin-depthstudyofgold(Col-vine,1989;Foster,1989;WuMeide,1989;HeShaoxun,1996).Notonlyshear-richSiO:strongrockcrushingandmylonitic,whiletheformationofporousandquartz-likecrystalsugarhole,butalsosoastogeneratenewminerals,mineralre-adjustandmakethemetaldispersionelementactivation,migration,mineralizationinfavorablelocations.Shearzonestructureisnotonlytheore-controllingfactors,butalsoimportantmetallogenicmechanism(WuMeide,etc.,1989).Gold-bearingshearzonetypegolddepositsareaclassofboththenumberofvein-typedeposits,includingsomedisseminatedtypedeposit,theshearmechanismandcontrollingfactorsforthemineralizationofthegolddeposit.Ramsayin1980,formallyandsystematicallyelaboratedlaterductileshearzone,manyscholarsathomeandabroadhavebeentheformationmechanismoftheductileshearzonewerecomplementarystudies(egListeretal,1984).Ramsay(1980)proposedcanbedividedintobrittleshearzone,aductileandbrittle-ductileshearzonethreecategories.Asearlyas1977,theBritishOuterHebrideSibsonstudythecharacteristicsofthrustfault,youmade​​alargedoublefaultrheologymodel.Onthestructurallevelislocatedintheuppercrust,generatedbythefrictionmechanismofrandomfabricfaultrocksformed.Thefollowingisadeepstructurallevelshearzone,generatedbytheplasticmechanismwithlinemanagementandthecompositionoffoliationfabriccomposedofmylonite.Andthetransitionphasebetweenthetwo,thetemperatureis250~350℃,themainductiledeformation,equivalenttogreenschistfacies.After,Mattauer(1980),Scholz(1988)andZhuZhicheng(1988)onthebasisofthemodelwassupplementedandimproved.Ductileshearzoneduringdeformation,resultinginalargenumberofmacroandmicrostructure,providesspaceforthegoldsolutionandthechannel.Sincestrainhardeningandtheriseinthecrustasmountainbuildingandotherreasonstobringinthesuperpositionofthebrittleductile,brittle-ductiledeformation,suchassuperimposedontheRiedelshearbeltfaultsystem.Thesesystemsareverygoodhoststructures.ManyveingoldtoproduceinsuchFracture.Shearzonewhiledrivingintothemigrationandconcentrationofminerals(Colvine,1989;Foster,1989;YueShietal,1990).Fluidpresentindifferenttypesandnatureoftheshearzone.ComponentstoCOz-H.Obased.Intheductileshearzone,metamorphicfluids,inparticular,isthedrivingforcesofteningplaystheroleofmetamorphicfluids,oftenformedinhigh-temperaturehydrothermalalteration.Inthebrittleshearzone,thesystemisanopensystem,water-rockinteractionisveryobvious,strongmaterialexchange,oftenformedinlowtemperaturehydrothermalalteration.Theresultofthefluid,oftenwiththeformationofmetasomaticalteration,waterbrecciazone,hydrothermalzone,micro-fracturezoneandthemineralizedzone.Fluidshearzonestendtocarryalargenumberofformingmaterials,andtobecomeore-formingfluids.Sourceofore-formingfluidhasacomplex,are:theintrusionofmagmacrystallizationreleasedduringdecompositionorfluid,metamorphicdehydrationprocessproducesvolatilefluidremoval,compactionortectoniccompressionresultingcontractionofthefluid,airorwaterunderrainfallProducedbyinfiltrationoffluidcirculation,theroleofthemantleresultingexhaustmetasomatismproducedfluidandthefluid.2.gold-bearingshearzoneevolutionBonnemaisonetal(1990)instudyingFrenchHercyniangold-bearingshearzonesofthebasementmadethethreeevolutionarystages.Theirworkshowsthatdepositsofeconomicimportancehaveoccurredintheshearzonecomplexmulti-stageevolutionaryrelated.Eachstagehasitsowncharacteristicsanduniquemineralsfromtherichgold.

2.1Theearlystages

Wherearetheroleofsheardeformation,inparticulartheroleofductile-brittledeformationhalftransformationoftherock,androckpermeabilitygreaterthan.Theyplayonthefluidchannels.Theroleofdeformationandhydrothermalrocksthejointresultedinthemineralcompositionandgeochemicalcompositionchangedsignificantly.Atthisstage,gold-bearingshearzonesarewelldevelopedchloriteandsilicification.Theintensityofsilicificationwiththestrengthanddeformationofthenumberofrepetitionsincreases.Whilechlorite,biotiteseparateTiO:,formingastoneorrutiletitaniumwhite.Howmanyofthesemineralcontentreflectstheintensityofhydrothermalstage.Whileinthehydrothermalalteration,associatedwithgoldintheschistositysurfacecrystallizationofpyrrhotite,thegoldcontentisusuallynothigh.Logoisagold-bearingpyritemineralsinthemyloniticrocksinsmallnumbers.Colvine(1989)andFoster(1989)thatthephaseoccursmainlyinamphibolitefaciesmetamorphicconditions,thealterationwasdisseminated,usuallydonotformdepositsofeconomicimportance.

Insomeareas,theevolutionfromductiledeformationtobrittle-ductiletransitionperiod,thatis,thephasetransitionfromamphibolitetogreenschistfaciesconditions,whenrelativelystronghydrothermalalterationtomaketheearlygold-bearingshearzonematurestage.Welldevelopedatthistimesilicification.Andformedthecoreofore-bearingstructures,gold-bearingpyriteandmarcasiteintopyrite,andthecorestructurefortheoretobringacertainnumberofFe,Cu,Zn,Sbandotherelements,especiallyelementsAs.Authorsbelievethat,Aselementsofthedegreeofdevelopmentisusuallyrelatedwiththebasementrocks,suchaslandinChinainthegold-bearingshearzonebeargolddepositswithintheverydevelopmentofgolddepositscontainarsenopyriteandarsenicincopperandothersulfur.

2.2mediumterm

Mid-stagegold-bearingshearzonesandshearzoneortheedgeofthepulse-likestructureappearsasthesymbol.Indeed,sinceearlystage,theshearleadstoshearbandproducedanumberoflocalspreadorexpansionconstruction,whichmakesthenumberofsulfidequartzveinswithdifferentfillinginit.Priorityofthesequartzveinsdevelopedinthesilica-richgranite,gneissandotheracidvolcanicrocksinsedimentaryrocks.

Theformationofshearbandsbymakingtheflowofhydrothermalore-rocksideofthesecretionofthephenomenonoccurred.Thetensionstructurenormallydoesnotcontainore.Whenthesestructureswithintheshearzoneoccurswhentheclockuptothewallsofthesestructurestoseetheearlystagesofmineralizationoccurredaslightactivation.Thesecanbere-activatedornewcrystallinequartztogeneratesmallparticlesofgoldsulfide,andifsuchactivationisnotwide,donotformeconomicallysignificantmineralization.Ifthegold-bearingshearzone,newactivitiescontinuetooccur,fillinginZhang'sfillingofthefaultzonewasbrokenagainandgiveprioritytomineralization,isthegold-bearingshearzonemarksthematurityofthemediumterm.Goldfromgold-bearingshearzonesofearlysulfide(gold-bearingpyrrhotiteorarsenopyrite)instabilityandtheemergenceofnaturalgoldhydrothermalfluidtransfertotheexpansionoftheformationofstructure.Thisisanimportanttimetoformgold.

Andmid-stagegold-bearingshearzoneassociatedsulfideparagenesis,thantheearlystagesofcomplex.Gold-bearingshearzonesinthematureperiod,alsoenteredtheSn,W,Bi,Moandotherelementsofthenewphase.Maturityofthegoldgradeofgoldisrelativelyhigh.Inthesulfide,thegolddidnotshowupwithaspecificpriorityassociatedmineralshaveanyrelationshipinwhichitcanbeaccompaniedbyanumberofmineralraw.Themediumtermtheearlystagesofmineralizationcanoverwriteallofmineralization,isrelativelydifficulttodistinguishbetweenthetwo.Onlyfromtheoriginalintopyrrhotiteandpyritemarcasiteleaf-shapedandwhenthefibrousstructurecanalsoprovethatpreviouslyexistedpyrrhotite.

2.3LateStage

Structureinthestretchmechanism,thegold-bearingshearzonedevelopedaseriesoftensilestructures,suchastensilecracks,stockworkandsoon,whichledtoanewmineralphaseproducedsignificantchanges.Mineralcrystalswillformalargenumberofsmallholesinthesesmallcrystalcave,ShaTang-likequartzcrystalsasfineparticlesfromre-shapedquartz.Atthistimetheparticlesofgoldwereproducedinmillimetersbetweenthequartzorquartzcrystalcave.Sulfidemineralsarestibniteleadwithsilver,silver,tetrahedrite,silverleadandantimonycrispflowofgalena,asilverandalargegoldmine.Thisstageischaracterizedbyincreasedsilvercontent.Althoughthisstagecanbetakentothespecialgold-richoresamples,butthemineralizationofeconomicsignificanceislimited.

Bonnemaisonetal(1990)Onthisbasis,thegold-bearingshearzoneisdividedintoearly,middleandlatethreetypes.Whichhaveeconomicsignificanceofthemainshearzonetypegolddepositsinthelatestagesoftheshearzoneiscloselyrelated.Earlystageinthelatestageofthefurtheractivationoftheinitialconcentrationofgoldtransferredtothefavorablespacesedimentarymineralization.Shearzoneinthelateformationtemperature,andthedeformationbehaviorisaresultofexpansionwiththeformationofgolddepositsinafavorablestage.Byearlyandmiddlestageismarkedbypyrrhotite,pyrite,marcasitereplacement(hightolowconversion),sugar,granularquartzoccur,andveinsandstockwork-likestructuregrowth(ductiletobrittletoughnessconversion)andsoon.Intheusualsenseofthelateshearzoneisequivalenttothebrittle-ductilephase.

Ductileshearzoneandonthegeneticrelationshipbetweengoldmineralizationandtype,andsomescholarsinthestudyofShandongPeninsulaandgold,hehadmadeandbrokenquartzveintypeofalteredrock,respectively,exquisitegoldandgoldfortheJiaojiarepresentative.Theformer,thelatterconstructionofthenextlevelofrelationship(YaofengLiangetal,1990).HeShaoxunetal(1996),ductileshearzoneinthestudyoftherelationshipwiththegoldisdividedintoductileshearzonetypegolddepositsandalteredfracturezone-typegolddeposit.Ductileshearzonetypegolddepositisformedbytheductileshearingofthedeposits,thedepositisstrictlycontrolledbytheductileshearzone,andductileshearbelthasthespaceandtimearegeneticallygolddeposits,suchasGuangdongHetaideposits(paragraphJiaruietal,1992;Liu,2006).Alteredfracturezonetypegoldisproducedintheductileshearzonesystem,thelatterformedbyhydrothermalalterationmineralizationofgolddeposits.Thedepositisonlyspacebetweentheshearzoneonly,thereisnotimeandcauseofthecontact.3.shearzonetypegoldmineralizationmodelBecauseofsuchdepositsbytheshearzone,appearsindifferentpartsofdifferentstructuralfabriccharacteristicsoftheore.Colvine(1989)andFoster(1989),respectively,andtheCanadianprovinceofSubiliergoldmineinZimbabwe,theoldmetamorphicrockproducedintheshearzonegolddepositsaredescribed,andtheestablishmentofashearzonegolddepositmodel.Subiliergoldproducedintheprovinceofgolddepositsandlarge-scalestrike-slipshearzoneinthedump.FormedinthelateArchean.Cutsheetsofgoldtoconstructlocated.Surroundingalluvialfluvialsedimentaryrocksofalongqualityalkalineintrusiverocksandvolcanicrocks.Metamorphicphaseandnotthedifferentdeformationconditions,thegoldveinstothegroupfromasingleclockpulseoutputisnot.Metamorphicrockalterationindifferentwithdifferentcharacteristics,reflectingthemineralcompositionisrelativelystable,themetamorphismisnotsuperimposed.TimetoreflectthelateArcheanshearzonesandregionalmetamorphismsimultaneous.

Throughtherocktodeterminethelevelofmetamorphismofthedepthofmineralization.Inamphibolitefaciesmetamorphism,thepyrrhotitesulphidealterationistypicalofthelackofgypsum,orrarely,tothemainductiledeformation.Orefabriclobular.Mineralizedfelsicrocksrelativetoearlier.Ingreenschistfacies,therockbrittleandductiledeformationischaracterizedby