Selenium Enrichment in Cambrian Stratabound Gold Deposits in the Western Qinling Mountains   总被引：1，自引：0，他引：1  

Liu Jiajun  Open Laboratory of Ore Deposit Geochemistry  Institute of Geochemistry  Chinese Academy of Sciences  Guiyang  Guizhou Zheng Minghu  Chengdu Institute of Technology  Chengdu  Sichuan Liu Jianming  Research Centre of Mineral Resources Exploration  Chinese Academy of Sciences  Beijing Zhou Yufeng  Gu Xuexiang  Zhang Bin  Lin Li  Chengdu Institute of Technology  Chengdu  Sichuan  Lu Wenquan Institute of Comprehensive Utilization of Mineral Resources  Chengdu  Sichuan 《《地质学报》英文版》1997,71(4):423-432

Stratabound gold deposits in the western Qinling Mountains occur in Cambrian chert formation composed of carbonaceous chert and carbonaceous slate. The distinctive chert formation provides important grounds for the mineralization and controls on the formation of gold deposits. Study shows that Se is exceptionally higher in both host rocks and gold orebodies. It may be recovered as a valuable component in ores for total utilization, and in some localities even independent Se orebodies (which are mined exclusively for Se) may be delineated. In gold ore Se mainly occurs as independent minerals or in the isomorphous form in sulphides and there is a positive correlation between Se and Au.  相似文献   

郭家岭型花岗岩地球化学特征与金矿化的关系   总被引：13，自引：0，他引：13       下载免费PDF全文

关康  罗镇宽  苗来成  黄佳展 《地质找矿论丛》1997,12(4):1-8

根据郭家岭花岗岩与成矿后岩脉的锆石ＳＨＲＩＭＰＵ－Ｐｂ年龄，金矿化被限定在１２６Ｍａ～１２０Ｍａ之间，结合岩体与金矿化密切的空间关系和岩石地球化学上的亲缘关系，认为招掖地区金矿化主要与郭家岭花岗岩有关，岩体高Ｎａ和Ｂａ，Ｓｒ是太古宙绿色岩区与金矿化有关花岗岩的一个明显的地球化学标志。  相似文献   

滇中砂岩铜矿成矿过程中水－岩反应的证据与机理   总被引：4，自引：0，他引：4  

庄汉平  冉崇英  何明勤  卢家烂 《地球科学》1996,(3)

从野外地质产状、岩石化学、有机岩石学、元素地球化学、有机地球化学等方面详细分析了滇中砂岩铜矿成矿过程中的水－岩反应证据，阐明了成矿过程中水－岩反应的机理，其中包括渗滤作用、扩散作用、混染作用、交代作用、交代溶蚀作用、氧化还原作用和沸腾作用  相似文献   

论易门铜矿区叠加钴矿化地质特征   总被引：10，自引：0，他引：10  

薛步高 《矿产与地质》1996,10(6):388-394

综合研究易门铜矿区钴、铜一钴矿床的矿化围岩及蚀变、矿石与脉石矿物组合、矿体地质特征等，提出易门铜矿区的钴矿化形成于晋宁期或印支－燕山期与隐伏的中－酸性岩体有关的后生叠加岩浆期后热液作用，还指出找矿方向，注意在隆起（背斜）与断裂构造的发育区，硅化、钠化、黑云母－绿泥石化蚀变带及Ｃｕ、Ｃｏ（Ａｕ）、Ａｓ、Ｐｂ、Ｚｎ化探异常的地段，优先找矿评价，扩大钴、铜－钴矿床的远景。  相似文献   

The Palaeomagnetic Study of the MineralizationAge of Gold Deposits in the Xiong'' ershan Area,Henan Province     

Wang Guanfu  Chen Zhihong  Ding Shiying  Ren FugenTianjin Institute of Geology  Mineral Resources  Tianjin  China 《《地质学报》英文版》1996,70(1):74-86

Based on palaeomagnetic studies of the Precambrian gold deposits in the Xiong'ershan area, Henan Province, the authors infer that the ore-forming processes of the Beiling alteration-type gold ore deposit and the Dianfang breccia-type gold ore deposit started in the Proterozoic, and was superimposed by later mineralization, whereas the mineralization age of the Jiguanshan quartz- vein type gold ore deposit is Yanshanian.  相似文献   

湖南外生金成矿特征及成矿区预测     

黎盛斯 《湖南地质》1996,15(1):29-32

外生金包括砾岩金和松散砂金，是外能作用在地表开放条件下形成的。在地壳发展过程中，动力学成矿的时空演化是连续的，但主要集中在早、晚元古代及早、晚古生代和中生代，而大发展于新生代。依据演化规律和矿化环境，提出５个找矿有望的外生金成矿带。  相似文献   

Time dependence of organic matter decay and mixing processes in Framvaren, a permanently anoxic fjord in South Norway     

David W. Dyrssen  Per O. J. Hall  Conny Haraldsson  Melissa Chierici  Jens M. Skei  H. Göte östlund 《Aquatic Geochemistry》1996,2(2):111-129

Three different layers have been identified in Framvaren, which has a maximum water depth of 184 m. One oxic layer above the redoxcline at 18–20 m. One anoxic layer from 20 to 100 m which is occasionally ventilated by a flow over the sill (which has a depth of 2.5 m), and finally a stagnant layer below 100 m. Using the release rate of silica from the bottom and measurements of the concentration of HTO it is possible to make some calculations on the annual volume of interleaving in the layers 25–50 m, 50–75 m, and 75–100 m together with the advective flows. Reliable values of the sulfide concentration were obtained by precipitating and weighing HgS together with careful protection of all anoxic water samples with argon. The light yellow color of the precipitate in the depth range 25 to 80 m indicates that the occasional ventilation will cause such reactions as 0.50₂ + H₂S S(colloidal) + H₂O. The elemental sulfur, being stabilized with HS^–, is set free upon the precipitation of HgS. The new data for the concentration of sulfide give an acceptable stoichiometry for the decay reaction of organic matter. This is not the case with the data of Yao and Millero. The mean values for the concentrations of ammonium and phosphate agree with the new data of Yao and Millero. The mol/mol C/N ratio of 10.1 found in trapped material by Naess and coworkers (1988) agrees with the stoichiometry of the dissolved constituents, i.e. C/N = 9.92 ± 0.45. A denitrification reaction is suggested to explain the high values of C/N. The vertical diffusion coefficient at 100 m calculated from the depth profile of silica was 0.92 × 10^–6 m² s^–1 which lies in the range of values given by Fröyland. Finally, the ¹⁴C age of the total dissolved inorganic carbon (Ct) in the water below 90 m was about 1600 years indicating a bioproduction in the period 8000 years B.P. to A.D. 1853 when a channel was opened between the fjord outside (Helvikfjord) and Framvaren.  相似文献   

Self-organization of recent rhythmic iron-manganese precipitations in underground mines in the Harz mountains     

S. Dietrich  K. -H. Jacob 《International Journal of Earth Sciences》1996,85(1):29-37

A recent early diagenetic banded iron-manganese mud has been forming underground in a closed lead-zinc mine for approximately 40 years. The processes leading to the banded structure of the precipitate were studied during a period of 2 years. Therefore, 19 physical and chemical parameters were measured regularly in short intervals. The resulting time series were analysed with respect to the data sets of the monthly chemical analyses of the descendent mine water, the daily rainfall and the mineral content. The results reveal that the precipitated material undergoes internal self-organization due to interaction of redox, colloid-chemical, microbial, electrical and ripening processes, and not exclusively produced by seasonal fluctuations of material input. Thus, the primary banding of the material, caused by externally forced fluctuations of the redox conditions within the mine water, is reorganized after a short time. The finally observed bands are controlled by non-linear coupling of reaction and transport processes within the mud. A genetic model for the banded mineralization was developed and verified by numerical simulation.  相似文献   

湘西沃溪金锑钨矿床中白云母的矿物学研究   总被引：3，自引：0，他引：3  

邵靖邦  王濮  陈代璋 《岩石矿物学杂志》1996,15(3):269-279

白云母广泛存在于矿床的各种赋矿围岩中。作者对各种地质产状及不同时期形成的白云母在矿床中的分布特征、化学成分及元素组合、晶体化学参数、晶胞参数、热分析特征、红外光谱学特征等进行了较详细的研究，找出了有矿化和无矿化及不同类型的矿化之间白云母的主要差别，确定了本矿床的白云母的标型特征，对找矿勘探具有重要的指导意义  相似文献   

吉木乃地区金矿成矿作用、类型和成矿模式   总被引：1，自引：1，他引：1  

谭克仁  贺伯初 《大地构造与成矿学》1996,20(1):67-70

本文深入阐述了新疆北部吉木乃地区金矿成矿作用的溶解，输运和沉淀成矿化学动力学机制，四种成矿类型和三层楼成矿模式。  相似文献