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1.
用LA-ICP-MS技术对北大别木子店地区细粒二长花岗岩脉中的锆石进行原位U-Pb年龄和Hf同位素测定,结果表明,该花岗岩形成于128.9±0.7Ma,为早白垩世岩浆活动的产物,在锆石中发现古元古代和新元古代的锆石核;锆石ε_(Hf)(t)介于-25.1~-19.2之间,平均值为-22.7,二阶段模式年龄T_(DM2)主要介于2115~2505Ma之间,2个继承锆石分析点分别给出了-10.5和6.5的ε_(Hf)(t)值,对应的二阶段模式年龄T_(DM2)分别为1151Ma和1709Ma。木子店地区细粒二长花岗岩脉的锆石年龄和Hf同位素特征表明,花岗岩为古元古代古老地壳物质部分熔融形成,岩石源区可能有中元古代地幔物质及太古宙古老地壳物质的贡献,形成于大别造山带从挤压向伸展的转换阶段。 相似文献
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桂东南大容山-十万大山S型花岗岩带的成因：地球化学及Sr-Nd-Hf同位素制约 总被引：11，自引：9，他引：11
本文报道桂东南大容山-十万大山花岗岩带浦北岩体(东北带)、旧州岩体(中部带)和台马岩体(西南带)全岩的主、微量元素、Sr-Nd同位素和锆石的LAM-MC-ICPMS原位Hf同位素分析结果。岩石学及元素地球化学结果显示:上述三个岩体为典型S型花岗岩;高I_(Sr)(>0.721)和低ε_(Nd)(t)(-13.0～-9.9)意味着它们可能来自古老地壳的重熔。岩浆结晶(～230Ma)锆石的ε_(Hf)(t)值主要集中在-11～-9,相应的T_(DM2)模式年龄为1.9～1.8Ga;少数结晶锆石的ε_(Hf)(t)值逐渐升高到-4.5,T_(DM2)降低为～1.5Ga。捕获锆石(1681～384Ma)的的ε_(Hf)(t)值分布在-17.1～ 3.4,T_(DM2)主要集中在2.4Ga、1.9Ga和1.5Ga。大部分岩浆结晶锆石ε_(Hf)(t)值与根据"全岩ε_(Nd)(t)值和‘地壳Hf-Nd相关’预测值"基本一致,表明平均地壳存留年龄为1.9Ga的地壳是最重要的物源区。部分岩浆锆石与捕获锆石具有相同的T_(DM2)～1.5Ga,表明平均地壳存留年龄为1.5Ga的物源区参与了该花岗岩带的形成;由于缺少T_(DM2)>2.0Ga的岩浆锆石,少量平均地壳存留年龄为2.4Ga的再循环地壳物质参与了该花岗岩带的形成。因为缺少显著幔源特征的高ε_(Hf)(t)值锆石,本文认为地幔物质基本没有参与该S型花岗岩带的形成。 相似文献
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《矿物岩石地球化学通报》2017,(1)
通过对福建紫金山地区不同岩石样品中岩浆锆石的SIMS U-Pb年龄和Hf、O同位素研究,对该地区岩浆序列以及源区组成、壳幔相互作用等进行初步探讨。结果显示,岩石样品中岩浆锆石的年龄(151~1514 Ma)较为分散,包含了从中元古代、震旦纪、早古生代晚期、晚三叠世到晚侏罗世的5个不同岩浆侵入时期。锆石的二阶段Hf亏损地幔模式年龄(t_(DM2)值)主要分布在古元古代,ε_(Hf)(t)数据也显示主要沿基性地壳演化线分布,指示古元古代时期的新生基性地壳可能是研究区中元古代直至晚侏罗世侵入岩形成的主要源区。锆石δ~(18)O及ε_(Hf)(t)值显示中元古代及震旦纪岩浆作用是幔源岩浆与古元古代基性地壳共同作用的结果;早古生代晚期和晚三叠世岩浆作用以壳源为主;至晚侏罗世,亏损地幔物质对岩浆作用的影响增加。 相似文献
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拉萨地块南部冈底斯岩浆带主要形成于中生代–早新生代(205~40 Ma),正的锆石ε_(Hf)(t)和全岩ε_(Nd)(t)显示了新生地壳组分的特征,其形成普遍被认为与新特提斯洋俯冲或印度–欧亚大陆碰撞后的板片断离有关。作者近期的研究工作显示,冈底斯岩浆带中部的早始新世挡顶拉和先弄错纳花岗质侵入岩具有明显的负ε_(Nd)(t)值。锆石LA-ICP-MS U-Pb年龄表明,上述侵入岩形成于~50 Ma,与冈底斯早新生代岩浆大爆发时期(~50 Ma)一致。挡顶拉和先弄错纳侵入岩具有轻稀土元素富集、重稀土元素亏损以及中等的负Eu异常特征,但先弄错纳岩体具有低的稀土元素总量和更明显的轻、重稀土元素分异。挡顶拉和先弄错纳侵入岩具有明显富集的Sr-Nd同位素组成:(~(87)Sr/~(86)Sr)i=0.7096~0.7121,εNd(t)=-7.3~-8.0。这些侵入岩主要可能来自古老地壳的重熔,且其源区组成矿物可能为黑云母+角闪石+石英+斜长石,岩浆在上升过程中经历了结晶分异。尽管目前的研究资料还无法解释这种富集的同位素特征是与拉萨古老地壳的部分熔融有关,还是与俯冲的印度古老大陆地壳物质熔融有关,但是明显负ε_(Nd)(t)值的花岗质岩石在拉萨地块南部冈底斯岩基中部的出现,有可能为新特提斯洋俯冲及印度–欧亚大陆碰撞过程提供新的启示。 相似文献
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湘东北三墩铜铅锌矿区花岗岩的岩石成因——锆石U-Pb测年、岩石地球化学和Hf同位素约束 总被引：1，自引：1，他引：0
对湘东北三墩铜铅锌矿区花岗岩进行了系统的锆石U-Pb年代学、岩石地球化学和Hf同位素分析。LA-ICP-MS锆石U-Pb定年表明,三墩铜铅锌矿区花岗岩成岩年龄为131.9±1.1Ma。三墩铜铅锌矿区花岗岩为一套强过铝质钙碱性系列花岗岩,富集U、Ta、Pb,亏损Ba、Nb、Sr、Zr、Ti等元素,稀土元素配分模式为右倾配分模式,具有弱负Eu异常。Hf同位素分析表明,三墩铜铅锌矿区花岗岩燕山晚期锆石ε_(Hf)(t)值为-5.9~-2.4,Hf同位素二阶段模式年龄为1558~1338Ma,表明其物质来源于中元古代古老地壳岩石部分熔融。749.5Ma继承锆石核的ε_(Hf)(t)值为+4.8,Hf同位素二阶段模式年龄为1355Ma,暗示其物质来源有幔源物质加入。三墩铜铅锌矿区花岗岩可能是由于中下地壳的熔融岩浆形成后,混入少量幔源物质上侵形成的。 相似文献
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云南格咱岛弧带休瓦促Mo W Cu矿床两期岩浆作用的锆石U Pb年龄、Hf同位素组成及构造意义 总被引：1，自引：0，他引：1
锆石LA-ICP-MS U-Pb定年结果显示,休瓦促Mo-W-Cu矿床含矿花岗闪长岩的形成年龄为202±3.5Ma,形成于甘孜-理塘洋壳向西俯冲时期;含矿二长花岗岩的形成年龄为83.3±1.7Ma,形成于燕山晚期造山后伸展环境。Hf同位素原位分析结果显示,花岗闪长岩中锆石的ε_(Hf)(t)值为-2.87~4.12(平均为0.09),T_(MD1)年龄541~828Ma,T_(DM2)年龄为719~1109Ma,表明岩体形成的物质来源除壳源物质之外,也有幔源物质的混入;二长花岗岩中锆石的ε_(Hf)(t)值为-7.96~-2.75(平均为-5.54),T_(MD1)年龄为820~1019Ma,T_(DM2)年龄为1102~1391Ma,ε_(Hf)(t)0,表明岩石是由古老地壳物质的部分熔融形成的产物。休瓦促两期含矿岩体的锆石U-Pb定年与Hf同位素原位分析显示,区内存在晚三叠世和晚白垩世两期构造-岩浆-成矿作用。晚三叠世花岗闪长岩岩浆侵入及Cu多金属成矿作用与洋壳俯冲造山有关;而晚白垩世二长花岗岩岩浆侵入及Mo多金属成矿作用主要形成于陆-陆碰撞造山的构造背景。研究表明,从晚三叠世洋壳俯冲造山至晚白垩世造山后伸展作用过程中都存在构造-岩浆-成矿作用的发生,且在晚三叠世构造-岩浆活动的基础上叠加了晚白垩世的成岩成矿作用,这为区内复合叠加成矿作用的研究提供了例证。 相似文献
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《西北地质》2021,(3)
白海子南岩体是库鲁克塔格地区典型的古生代花岗质侵入岩。深入了解该岩体岩石成因及物质来源,对研究库鲁克塔格地区构造背景及古生代地壳演化过程具有重要意义。笔者对白海子南岩体进行了系统的全岩Sr-Nd和锆石Hf同位素及锆石微量元素研究。结果表明,该岩体具有中等I_(Sr)(0.710 01～0.712 87)比值,富集的ε_(Nd)(t)值(-21.01～-18.07)和ε_(Hf)(t)值(-26.55～-17.28),对应的Nd二阶段模式年龄(T_(DM2))和Hf模式年龄(T_(DMC))分别为2.60～2.84 Ga和2.43～3.00 Ga,表明其是古元古代早期—新太古代地壳物质再循环的产物。锆石微量元素分析表明,该岩体锆石为壳源岩浆锆石,T_(Zr)均值为745℃,T_(Ti)均值为692℃,属于"冷"岩浆,岩体形成于主动大陆边缘,是南天山洋向南俯冲到塔里木克拉通之下后期阶段的产物,俯冲过程中幔源岩浆底侵产生的余热为该岩体熔融提供热源。在库鲁克塔格地区发现多期次古生代花岗质侵入岩,这些岩体的ε_(Nd)(t)值和锆石ε_(Hf)(t)值随年龄的减小呈现先上升后下降的趋势,结合前人已有资料,推测在南天山洋向塔里木克拉通俯冲过程中,库鲁克塔格地区奥陶纪—早石炭世地壳演化经历了先减薄再加厚的演化过程。 相似文献
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湖南七宝山铜多金属矿床石英斑岩时代与成因:锆石U-Pb定年及Hf同位素与稀土元素证据 总被引：1，自引：0，他引：1
湖南浏阳七宝山铜多金属矿床位于钦杭成矿带西段,是湘东北规模最大的铜多金属矿床。矿床的形成与区内的石英斑岩关系密切。石英斑岩内锆石具有岩浆锆石特征,LA-ICP-MS锆石U-Pb定年结果为155~153 Ma,代表其形成年龄,属晚侏罗世岩浆活动产物。岩浆锆石的~(176)Hf/~(177)Hf=0.282296~0.282603,εHf(t)=–12~–2.7,平均地壳模式年龄tDM2=1377~2056 Ma;锆石ΣREE=496~4162μg/g,(Yb/Nd)N=71.9~3133.8,HREE强烈富集,具有强烈Ce正异常(δCe=1.68~203.13)和强烈至中等Eu负异常(δEu=0.05~0.67),表明石英斑岩的岩浆源区具有明显壳源特征,来自于古元古代至中元古代地壳的部分熔融。结合岩石学研究,七宝山矿区石英斑岩的形成除了中下地壳冷家溪群或更古老的基底物质的部分熔融外,还有幔源组分加入,这一期岩浆与成矿作用与岩石圈拆离和软流圈物质上涌及随后的玄武岩底侵作用有关。 相似文献
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大兴安岭中段索伦地区白音高老组火山岩锆石U-Pb年龄、地球化学特征及构造意义 总被引：3，自引：2，他引：1
白音高老组火山岩位于大兴安岭中段科右前旗索伦地区,主要岩性为流纹岩和流纹质晶屑凝灰岩。LA-ICP-MS锆石U-Pb同位素分析表明,3组样品的锆石U-Pb年龄分别为127±2Ma、133±2Ma和123±1Ma,即白音高老组火山岩形成于133~123Ma,为早白垩世岩浆活动的产物。岩石学和岩石地球化学特征显示,白音高老组火山岩类似于高分异的I型花岗岩,有斜长石和少量角闪石部分熔融残留。锆石的~(176)Hf/~(177)Hf值介于0.282854~0.283026之间,ε_(Hf)(t)为较高的正值,变化于+5.5~+11.5之间,Hf二阶段模式年龄(T_(DM2))为828~439Ma,表明兴安地块地壳的主体增生年代为新元古代—显生宙。通过对比东北地区(以邻区为主)同时代岩浆-构造活动,研究区内白音高老组火山岩形成于伸展构造环境,这种伸展构造环境的形成可能与古太平洋板块俯冲于欧亚大陆之下的弧后伸展环境有关。 相似文献
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本文对出露在兴凯地块南部伊曼群的变沉积岩和侵入其中的火成岩进行了系统的锆石LA-ICP-MS U-Pb定年和Hf同位素研究,旨在查明伊曼群的形成时代与物源,并讨论侵入岩的成因和构造背景。伊曼群二云母片岩中锆石呈自形-半自形,显示典型的岩浆生长环带,暗示其岩浆成因。定年结果表明:100个碎屑锆石分析点给出了555～1322Ma的年龄区间,主要峰值年龄为555Ma、612Ma、700Ma、739Ma、769Ma、839Ma、936Ma;其中约533Ma的锆石ε_(Hf)(t)值介于-4.1～+3之间,二阶段模式年龄t_(DM2)介于1305～1755Ma之间;700～839Ma的锆石ε_(Hf)(t)值介于-3.7～+7.8之间,二阶段模式年龄t_(DM2)介于1246～1907Ma之间。侵入伊曼群的白云母二长花岗岩的定年结果显示为443±3Ma,此年龄对应ε_(Hf)(t)值介于-17.6～-4.2之间,二阶段模式年龄t_(DM2)介于1688～2529Ma之间。结合二云母片岩中碎屑锆石的最小年龄以及穿切其中花岗岩的形成时代,可以判定伊曼群二云母片岩的形成时代介于443～555Ma之间,应为新元古代晚期至晚奥陶世之间。基于伊曼群中碎屑锆石的年龄众数及与区域岩浆事件的对比,伊曼群的沉积物源主要来自松嫩地块和佳木斯地块的新元古代火成岩。此外,白云母二长花岗岩显示出埃达克岩的地球化学属性,岩浆源于加厚下地壳的部分熔融,暗示晚奥陶世研究区可能发生了陆壳加厚事件。 相似文献
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Influences of the unsaturated,saturated, and riparian zones on the transport of nitrate near the Merced River,California, USA 总被引：1，自引：0，他引：1
Joseph L. Domagalski Steven P. Phillips E. Randall Bayless Celia Zamora Carol Kendall Richard A. WildmanJr Janet G. Hering 《Hydrogeology Journal》2008,16(4):675-690
Transport and transformation of nitrate was evaluated along a 1-km groundwater transect from an almond orchard to the Merced River, California, USA, within an irrigated agricultural setting. As indicated by measurements of pore-water nitrate and modeling using the root zone water quality model, about 63% of the applied nitrogen was transported through a 6.5-m unsaturated zone. Transport times from recharge locations to the edge of a riparian zone ranged from approximately 6 months to greater than 100 years. This allowed for partial denitrification in horizons having mildly reducing conditions, and essentially no denitrification in horizons with oxidizing conditions. Transport times across a 50–100-m-wide riparian zone of less than a year to over 6 years and more strongly reducing conditions resulted in greater rates of denitrification. Isotopic measurements and concentrations of excess N2 in water were indicative of denitrification with the highest rates below the Merced River. Discharge of water and nitrate into the river was dependent on gradients driven by irrigation or river stage. The results suggest that the assimilative capacity for nitrate of the groundwater system, and particularly the riverbed, is limiting the nitrate load to the Merced River in the study area. 相似文献
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山西五台山区滹沱群变质玄武岩岩石学、地球化学特征及其成因意义 总被引：10，自引：0，他引：10
在野外地质调查的基础上,选取滹沱群豆村亚群底部四集庄组玄武岩、顶部青石村组玄武岩和东冶亚群中下部河边村组玄武岩,进行岩石学和地球化学研究。分析结果表明：玄武岩主量元素高TiO2、TFeO,低MgO,具有演化的基性岩浆的特征。稀土元素含量相对较高,具有弱—中等程度的轻稀土元素富集,中等程度的轻重稀土元素分异,轻微的Eu异常;玄武岩中Cr、Ni含量变化较大,但与Mg#具有很好的正相关性。微量元素配分图解中具有明显的Sr负异常,部分样品具有Nb、Ta和Ti负异常,无Zr、Hf负异常,与岛弧火山岩不同;同时Nb、Ta无分异,Zr/Hf值较高,具有板内玄武岩浆的特征。综合分析认为,滹沱群玄武岩可能形成于板内裂谷环境。在岩浆上升过程中发生橄榄石与尖晶石的分离结晶作用,同时不同程度地受到地壳的混染。 相似文献
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以出露在西藏南木林县秦马弄地区二长花岗岩体为研究对象,从野外地质调查、岩石学、LA-ICP-MS锆石U-Pb定年、元素和Lu-Hf同位素地球化学等方面对其进行了分析研究。结果显示：秦马弄地区二长花岗岩体类似于A型花岗岩,形成于古近纪(E1),其LA-ICP-MS锆石U-Pb年龄为(62.0±0.5)~(63.0±0.5) Ma;岩体形成的温度较高(锆石饱和温度为745~805 ℃,平均766 ℃);岩石富SiO2(72.6%~75.0%)、Na2O(2.86%~3.59%)和K2O(4.12%~5.25%),贫CaO(0.72%~1.39%)和MgO(0.26%~0.36%),高FeOT/MgO值(7.26~10.3),属高钾钙碱性系列,弱过铝质;岩石具明显的负Eu异常(Eu/Eu*=0.40~0.70),普遍表现出Ba、Sr、P、Ti元素的亏损和Rb、Th、K、Zr、Hf元素的富集。εHf(t)值为-4.7~-1.8,其两阶段地壳Hf模式年龄tDM2为(1.1~1.3) Ga。秦马弄A型花岗岩体是冈底斯基底地壳物质部分熔融的岩浆产物,形成于古近纪印度板块与欧亚板块俯冲碰撞引起的总体为岛弧背景下的局部拉张构造环境。 相似文献
16.
扬子北缘马元铅锌矿床闪锌矿微量元素及S-Pb-He-Ar-C同位素地球化学研究 总被引：7，自引：3，他引：4
马元铅锌矿床是近年扬子陆块北缘铅锌找矿的新突破。矿体呈层状、似层状产于碑坝隆起翼部震旦系灯影组角砾状白云岩层间构造带中,围岩蚀变很弱。矿石中硫化物以闪锌矿、方铅矿为主,中粗粒晶质结构,充填于白云岩角砾间。闪锌矿富集Cd、Ge、Ag,贫In、Tl、Se,Ga/In为6~132,Ge/In多1000,成矿温度以中-低温为主。金属硫化物ε~(34)S值相对集中,为12.9‰~19.4‰,平均为17.4‰,来自于海相硫酸盐的还原。铅同位素组成稳定,~(206)Pb/~(204)Pb为17.858~17.918:~(207)Pb/~(204)Pb为15.603~15.694;~(208)Pb/~(204)Pb为37.756~38.046,具有造山带和上地壳铅的特征,震旦系可能提供了金属成矿物质。闪锌矿中流体包裹体的~3He/~4He为0.03Ra~1.05Ra,~(40)Ar/~(36)Ar为326.1~765.1,~(38)Ar/~(36)Ar为0.183~0.204,表明成矿流体主要为地壳流体和饱和大气水(大气降水或海水)的混合。闪锌矿内流体包裹体挥发分δ~(13)C_(CH_4)值为-36.01‰~-28.80‰,δ~(13)C_(C_2H_6)值为-27.72‰~-22.44‰,δ~(13)C_(CO_2)值为-23.24‰~-9.68‰,表明有机流体参与了成矿作用。石英、方解石的H-O同位素结果表明具有海水和有机水混合的特征。可见,成矿流体具有两种流体混合的特征,一为蒸发海水与围岩反应所形成的盆地卤水,二为有机流体。推测矿区可能存在一个古油气藏,由于TSR生成一高硫气藏,为区内还原性有机流体的主要来源。当富含Pb、Zn等成矿物质的成矿流体运移至富含CH_4和H_2S的还原性流体的矿区角砾岩带时,两种流体混合,Pb、Zn等遇到H_2S发生反应而沉淀成矿,并伴生热液白云石等,形成了马元铅锌矿床。综上所述,我们认为马元矿床属MVT型铅锌矿床。 相似文献
17.
I. A. Tararin V. M. Chubarov E. K. Ignat’ev S. V. Moskaleva 《Russian Journal of Pacific Geology》2007,1(1):82-97
The geology and mineralogy of host metamorphic rocks, the mineralogy of sulfide ores, and the distribution of PGE mineralization were studied in detail for the Kvinum-1 and Kvinum-2 copper-nickel occurrences of the Kvinum ore field, which are the most promising targets for the copper-nickel-PGE mineralization of the Sredinny Range of Kamchatka. It was established that stringer-disseminated and massive copper-nickel ores are localized in amphibole peridotites, cortlandites, and form ore bodies varying from tens of centimeters to 5–20 m thick among the layered cortlandite-gabbroid massifs. The massive sulfide ores were found only at the bottom of cortlandite bodies and upsection grade into stringer-disseminated and disseminated ores. Pyrrhotite, chalcopyrite, and pentlandite are the major ore minerals with a sharply subordinate amount of pyrite, sphalerite, galena, arsenopyrite, and löllingite. Besides pentlandite, the Ni-bearing minerals include sulforasenides (gersdorffite), arsenides (nickeline), and tellurides (melonite) of nickel. It was found that PGE mineralization represented by antimonides (sudburyite) and tellurobismuthides (michenerite) of Pd with sharply subordinate platinum arsenide (sperrylite) is confined to the apical parts of massive sulfide zones and the transition zone to the stringer-disseminated ores. Ore intervals enriched in arsenides and tellurides of Ni, Pd, and Bi contain high-purity gold. In the central parts of the orebodies, the contents of PGE and native gold are insignificant. It is suggested that the contents of major sulfide minerals and the productivity of PGE mineralization in the cortlandites are defined by combined differentiation and sulfurization of ultramafic derivatives under the effect of fluids, which are accumulated at the crystallization front and cause layering of parental magmas with different sulfur contents. The fluid-assisted layering of mafic-ultramafic massifs resulted in the contrasting distribution of PGM in response to uneven distribution of sulfur (as well as As, Te, and Bi) during liquid immiscibility. The productivity of PGE mineralization significantly increases with increasing contents of S, As, Te, and Bi (elements to which Pt and, especially, Pd have high affinity) in fluids. 相似文献
18.
A geophysical survey was conducted to determine the depth of the base of the water-table aquifer in the southern part of
Jackson Hole, Wyoming, USA. Audio-magnetotellurics (AMT) measurements at 77 sites in the study area yielded electrical-resistivity
logs of the subsurface, and these were used to infer lithologic changes with depth. A 100–600 ohm-m geoelectric layer, designated
the Jackson aquifer, was used to represent surficial saturated, unconsolidated deposits of Quaternary age. The median depth
of the base of the Jackson aquifer is estimated to be 200 ft (61 m), based on 62 sites that had sufficient resistivity data.
AMT-measured values were kriged to predict the depth to the base of the aquifer throughout the southern part of Jackson Hole.
Contour maps of the kriging predictions indicate that the depth of the base of the Jackson aquifer is shallow in the central
part of the study area near the East and West Gros Ventre Buttes, deeper in the west near the Teton fault system, and shallow
at the southern edge of Jackson Hole. Predicted, contoured depths range from 100 ft (30 m) in the south, near the confluences
of Spring Creek and Flat Creek with the Snake River, to 700 ft (210 m) in the west, near the town of Wilson, Wyoming.
Received, May 1997 · Revised, February 1998 · Accepted, April 1998 相似文献
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E. M. Prasolov S. A. Sergeev B. V. Belyatsky E. S. Bogomolov K. A. Gruzdov I. N. Kapitonov R. Sh. Krymsky V. O. Khalenev 《Geochemistry International》2018,56(1):46-64
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others. 相似文献