华北地台北缘东段金矿床氢氧同位素地球化学研究

华北地台北缘与金矿床有关的花岗岩类以贫D为特征,由其衍生的岩浆水δD=—120‰——85‰,δ~(18)O=5.0‰—8.0‰。H,O同位素研究表明,太古宙绿岩建造金矿床成矿流体为地壳深处多源混合水,以δD,δ~(18)O十分稳定为特征;显生宙花岗岩建造金矿床成矿流体为与金铜系列花岗岩再平衡的岩浆水;火山岩建造金矿床成矿流体为大气降水与岩浆水的混合产物,以δ~(18)O的明显漂移为特征;古生代绿岩建造金矿床的成矿流体为被花岗岩侵入体加热的大气降水,以δD特别低为特征。     

印度尼西亚戴里Sedex型铅锌矿集区成矿流体特征及成矿物质来源:流体包裹体及同位素地球化学证据

戴里铅锌矿集区位于印度尼西亚苏门答腊岛西北部,是一个主要产于页岩、具有巨型规模的Sedex型铅锌矿。通过系统的流体包裹体测试及H、O、S、Pb等同位素分析,以对其成因进行约束。分析结果表明:①戴里铅锌矿流体包裹体均一温度范围为189~315℃,峰值为220~240℃;②δD_V-SMOW值范围为-68.7‰~-76.4‰,平均为-72.9‰,δ18O_V-SMOW值范围为+5.9‰~+19.5‰,平均为+16.6‰;③黄铁矿δ34S_CDT值为正值,集中分布在+25.49‰~+26.36‰之间;④铅同位素显示较高的μ值（9.92~10.17,平均值为10.04）和ω值（38.06~40.51,平均值为39.26）。该矿床成矿流体温度为中温（220~240℃）,成矿流体可能以岩浆水为主,有少量浅源水的加入,硫、铅均为单一来源,其中硫主要来自海水,铅来源于上地壳。      

雪峰山中段淘金冲金矿床氢氧同位素特征

本文通过对淘金冲金矿区地质特征和主成矿阶段石英氢氧同位素组成研究,对淘金冲金矿成矿流体来源进行了探讨。研究结果显示淘金冲金矿床成矿流体δDH20‰值介于-97‰~-44‰,δ18OH20‰值介于-2.04‰~+8.92‰,成矿期第Ⅰ阶段及第Ⅱ阶段成矿流体以岩浆水和变质水混合为主,第Ⅲ阶段随着成矿环境逐渐开放,温度压力降低,大气降水逐渐占主导地位。     

内蒙古金厂沟梁金矿床成矿流体特征及稳定同位素研究

对金厂沟梁金矿床含金石英脉中流体包裹体进行了岩相学、显微测温、单个包裹体的激光拉曼测试以及O和S同位素组成等方面研究。结果表明,成矿流体气相成分主要为H2 O,属H2 O-NaCl体系,包裹体均一温度为148.7℃～352℃,盐度[ w （ NaCl ）/％]为1.05％～5.99％。δ18 O值为-1.1‰～3.0‰,说明成矿流体继承了变质流体的特征,仍以岩浆水和后期大气降水为主;δ34 SV-CDT组成为0.6‰～4.3‰,平均值0.817‰,极差为3.1‰,表明成矿流体中的硫主要来自于幔源,其次为围岩。综合分析认为,金厂沟梁金矿床是在燕山晚期太平洋板块俯冲导致岩石圈的快速减薄、拆沉的拉张环境下形成的浅成造山型金矿。     

凡河元古宙拗拉谷关门山铅锌矿床成因研究

凡河元古宙拗拉谷属地幔活化型中的克拉通拗拉谷。从长石石英砂岩—碳酸盐岩—细碧岩组合到石英砂岩—碳酸盐岩—页岩组合序列,表明它是一个夭折的裂谷。关门山铅锌矿床矿物组成简单,多次沉淀,有溶蚀、交代及分带现象。矿石包裹体成分及氢氧同位素组成表明成矿流体属大气降水混合的Na—Ca—Cl型盆地地层水,成矿温度为150—300℃。铅同位素表明成矿物质来自上地幔或下地壳,大约在1900Ma从源区分离出来进入太古宙结晶基底。硫同位素表明硫源相当海水硫酸盐,保存在成岩时由晶间水、孔隙水、软泥水集中起来的层间水里。矿床特征及稳定同位素表明成矿组分的迁移有早期的动静结合的混合模式与晚期的还原硫模式二种,沉淀也有早期的贱金属流体与H,S流体混合机制与晚期的pH值改变、温度降低,溶液稀释机制二种。成矿与基底隆起、基底断裂、盖层断裂、层位、岩性、古水文条件等有着密切的关系。矿床类型属密西西比河谷型后生矿床。     

纳日贡玛铜钼矿床地质特征及成因类型探讨

通过分析纳日贡玛铜钼矿床成矿地质背景、含矿斑岩体及矿床地质特征、流体包裹体及同位素地球化学特征等系统资料,并通过与玉龙斑岩型铜钼矿床的对比,认为纳日贡玛铜钼矿床成因类型为斑岩型铜(钼)矿床。     

栖霞市马家窑金矿床成矿流体地球化学特征

马家窑金矿床是胶东地区比较典型的石英脉型金矿床代表，属中低温热液矿床，成矿流体盐度较低，气相成分以H2O，CO2为主，其次是Na^＋，Ca^＋和Cl^-，K^＋和F^-较贫，流体的成分与大气降水热液相类似。成矿流体的H，O同位素值则反映大气降水在不同温度和不同水／岩值条件下与栖霞超单元回龙夼单元交换后的分布特征，认为马家窑金矿床的成矿热液属大气降水成因。     

造山型金矿床地质背景、地球化学特征和成矿模型研究综述

造山型金矿床与造山事件在时间和空间上具有十分密切的联系,对造山型金矿床的主要成矿时期、在世界和中国的分布规律、矿床地球化学特征以及成矿模型进行了总结.造山型金矿床成矿时间与大陆地壳生长过程中产生的热事件对应,主要形成于陆缘增生造山带,少量形成于陆－陆碰撞造山带.造山型金矿床的成矿流体具有低盐度(６％~１２％)、富 CO２(１０％~５０％)的特征,可以与其他类型的金矿床进行区分.就地球化学特征而言,不同时代不同地区差别较大,如太古宙与元古宙造山型金矿床成矿流体的δ１８O 值集中在６‰~１１‰、δ１３C值变化范围为０~－１０‰,而显生宙造山型金矿床δ１８O 值为７‰~１３‰、δ１３C值为０~－１０‰;太古宙造山型金矿床中硫化物的δ３４S值集中在０~９‰之间,而显生宙造山型金矿床则集中于０~１０‰之间;各时代造山型金矿床成矿流体均相对富集 D同位素,δD值集中于－８０‰~－２０‰之间.Pb和Sr同位素虽然在示踪物质来源方面研究进展较大,但是仍不能很好地指示造山型金矿床成矿物质的来源.随着研究的不断深入,地壳连续模式、变质脱挥发分模式、断层阀模式以及盆地尺度两阶段模式等成因模式先后被提出,用于描述造山型金矿床的形成过程,但关于造山型金矿床的成矿模式仍存在较大争议.      

伊朗松贡铜钼矿床研究新进展

松贡铜钼矿床位于伊朗西北部,是特提斯成矿域中的超大型斑岩型铜矿床之一。资料表明,松贡矿床矿石储量为
6.50亿t,其中含铜0.76%,钼0.01%。斑岩体呈岩株及岩墙状产出,铜钼矿化主要与花岗闪长斑岩有关,石英二长斑岩内也有少
部分矿化,在侵入体外围的碳酸盐岩中还有矽卡岩型矿化,松贡斑岩型铜钼矿床的成矿年龄约为20Ma。Cu矿化主要分布在钾化
带及部分绢英岩化带,以浸染状的形式出现在脉体及脉体晕中;在浅部,多数硫化物都被淋滤掉,铜蓝、辉铜矿及方辉铜矿等出现
在氧化带盖层下面。流体包裹体和稳定同位素(C、H、O、S)研究表明,与矿化有关的流体主要为岩浆水,后期有大气水加入(最多
占混合流体的20%)。      

滇东南洒西钨铍矿床成矿流体来源和演化: 来自流体包裹体和H-O同位素证据

洒西钨铍矿床位于滇东南老君山钨锡多金属成矿区。确定早期似层状矿体和晚期脉状矿体的流体性质、来源和演化过程, 并对其流体地球化学和同位素进行约束, 可以有效探讨洒西钨铍矿床成矿机制, 为老君山矿集区下一步找矿工作提供理论思考。洒西钨铍矿床脉状矿体的形成经历了硅酸盐阶段、氧化物-硫化物阶段和碳酸盐-萤石阶段, 白钨矿和绿柱石主要形成于前两阶段。对洒西钨铍矿床脉状矿体不同阶段石英中的流体包裹体进行了岩相学特征、显微测温、激光拉曼光谱分析等研究, 并对早期似层状矿体和晚期脉状矿体矿石中石英的氢-氧同位素组成进行了测试。结果表明: 该矿床内脉状矿体的流体包裹体主要有富液相包裹体、富气相包裹体和含子矿物多相包裹体3种类型。流体包裹体的气相成分以H₂O主, 含少量还原性气体如C₂H₂等, 液相成分也以H₂O为主。从硅酸盐阶段到碳酸盐-萤石阶段, 包裹体的均一温度和盐度(NaCl_eq)峰值范围分别为240~360℃、2.35%~13.81%;220~310℃、4.03%~9.86%和190~270℃、2.41%~6.88%。从硅酸盐阶段到碳酸盐-萤石阶段, 成矿流体的温度呈现降低趋势, 盐度也呈降低趋势。成矿流体总体上属中-高温度、低盐度、贫CO₂、含部分还原性气体的NaCl-H₂O流体体系。早期似层状矿体石英样品δD_V-SMOW值变化范围小, 为-102.8‰~-99.0‰, δ18O_V-SMOW值为11.7‰~13.0‰, δ18O_H2O值为3.16‰~6.46‰; 晚期脉状矿体氧化物-硫化物阶段石英样品δD_V-SMOW值变化范围较大, 为-99.6‰~-69.5‰, δ18O_V-SMOW值为11.2‰~14.1‰, δ18O_H2O值为3.08‰~6.73‰。综合表明成矿流体主要是岩浆水, 混合有少量大气降水或有机水, 流体可能发生了沸腾作用, 加之温度的降低, 导致晚期脉状矿体氧化物-硫化物阶段主要成矿物质的沉淀。洒西钨铍矿床属于中高温热液矿床。      

Foreword

正Rapid changes of Arctic sea ice cover have been in the focus of the international climate research community in recent years.Quite a few of nations have completed a large number of related surveys and research projects in the Arctic Ocean.Up to now,China has performed six research cruises to the Arctic Ocean resulting in a significant volume of research output.Improved knowledge on the atmospheree-sea ice-ocean interactions in the Arctic is a     

Exposure ages and radiogenic ages of ureilite(GRV 024516) and ordinary chondrite(GRV 024517) from Antarctica

The GRV 024516 and GRV 024517 meteorite samples collected from Grove Montains,Antactica are ureilite and H5 ordinary chondrite,respectively.Based on the study of mineralogy-petrology,the cosmic-ray exposure ages and gas retention ages of these two meteorites were determinated and calculated.Their cosmic-ray exposure ages are 33.3 Ma,51.7 Ma,and gas retention ages are 1936.8 Ma and 3720 Ma,respectively.The ureilite contains diamond,graphite and amorphous C,which are mainly carrier of noble gases indicating obviously shock metamorphism effects,which induced 40Ar partial loss.The H5 chondrite indicates thermal metamorphism of parent body,its gas retention age fall the range between 3220 Ma and 4510 Ma of the least shocked H5 chondrites     

Carbon storage and sequestration of national key ecological restoration programs in China: An introduction to special issue

<正>Although a crucial objective of ecosystem management should be the avoidance of degradation at the beginning,an unfortunate truth is that ecosystems have been substantially exploited,degraded and destroyed in the last century as a result of the global increase in economic and societal prosperity(Suding,2011).More than 60%of ecosystems have been converted for human use or degraded through unsustainable harvest,pollution,     

Guide for contributors

正The journal of Global Geology(English Edition)is sponsored by the International Center of Geoscience Research and Education in Northeast Asia,Jilin University of China(ISSN 1673-9736,CN22-1371/P).The former name of the journal was the Journal of International Geoscientific Research in Northeast Asia.It was launched in 1998 and served the scientists and teachers in     

Journal O f Ocean University of China(Oceanic and Coastal Sea Research)Article Index to Vol.13, 2014

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Journal of Mountain Science(JMS)

<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press     

Snow water content estimation from measured snow temperature

The vertical temperature profiles of snow and sea ice have been measured in the Arctic during the 2nd Chinese National Arctic Research Expedition in 2003(CHINARE2003).The high-resolution temperature profile in snow is solved by one-dimensional heat transfer equation.The effective heat diffusivity,internal heat sources are identified.The internal heat source refers to the penetrated solar radiation which usually warms the lower part of the snow layer in summer.By temperature gradient analysis,the zero level can be clarified quantitatively as the boundary of the dry and wet snow.According to the in situ time series of vertical temperature profile,the time series of water content in snow is obtained based on an evaluation method of snow water content associated with the snow and ice physical parameters.The relationship of snow water content and snow temperature and temporal-spatial distribution of snow water content are presented     

REPORT ON PONTONIINE SHRIMPS（CRUSTACEA：DECAPODA）COLLECTED BY JOINT CHINESE—GERMAN MARINE BIOLOGY EXPEDITIONS TO HAINAN ISLAND,SOUTH CHINA SEA i.ANCHISTUS,CONCHODYTES,CORALLIOCARIS

The present paper reports 7 species of pontoniine shrimps collected from Hainan Island,South China Sea,by the Joint Chinese-German Marine Biology Expeditions,in which,Conchodytes nipponensis(De Haan,1844)and Coralliocaris brevirostris Borradaile,1898 are new records from Chinese waters.