四川若尔盖北部寒武系太阳顶群硅质岩的热水沉积成因     

姜琦刚 《吉林大学学报(地球科学版)》1992,(4)

四川若尔盖北部寒武系太阳顶群为金矿矿源层,硅质岩为其中的主要组成部分.研究矿源层的成因,硅质岩成因是关键所在.硅质岩已遭受变质成为微晶石英岩,以块状为主.岩石中均含有不等量的有机碳.岩石中还保留了较多的沉积组构.主要化学成分以SiO_2为主,结合微量元素及稀土元素等综合研究表明,太阳顶群硅质岩为热水沉积成因,硅可能来自下伏及深部地层.  相似文献   

从29届地质大会看矿床地质学研究的进步   总被引：4，自引：0，他引：4  

翟裕生 《地质科技情报》1992,11(4):1-7

本文全面概括地介绍了第29届国际地质大会有关矿床地质学的进展和发展趋势,重点对海底热水成矿、浅成低温热液金矿和黑矿型矿床新模式作了详细介绍,此外也对成矿流体、矿床成因理论、矿床实验研究、矿床形成环境和演化规律,以及隐伏矿床的勘查方法等方面作了简要介绍。地幔流体研究和区域成矿学日益受到重视,一些新的基础理论,如化学动力学、表面化学、耗散结构、分形几何学以及非线性热力学和动力学等开始引用于矿床学研究。同位素地球化学方法在勘查中的应用有较明显的进展。矿床学研究的4个重要趋势是:1．向宏观发展:如地球历史中成矿作用的时空演化和成矿的大地构造背景;2．向微观深入:如同位素地球化学、成矿实验和水—岩作用机理的研究;3．成矿多来源、多成因和多阶段的研究;4．现代成矿作用与古老成矿作用的对比研究。  相似文献   

压碎台测定矿物包裹体在寻找内生金矿床中的应用     

孙中庆  徐明文 《地质科技情报》1992,(4)

本文综述了液态包裹体压碎法的机理以及该方法在寻找热液型金矿中的应用,例举了用该方法判别岩石的含金性、圈定蚀变晕的空间位置等方面的实例。  相似文献   

The evidence from inclusions in pumices for the direct degassing of volatiles from the magma to the hydrothermal fluids in the Okinawa Trough     

Yu?ZenghuiEmail author  Zhai?Shikui  Zhao?Guangtao 《中国海洋大学学报(英文版)》2002,1(2):171-175

This article presents the evidence in support of the direct magma degassing as the principal mechanism of volatiles releasing into the hydrothermal fluids in the Okinawa Trough, as contrasted to the argument for the hydrothermal stripping of volatiles from the volcanic rocks. Laser Raman microprobe and stepped-heating techniques are employed to determine the compositions and contents of the volatiles in pumices in the middle Okinawa Trough. The results show that the volatiles are similar to the gases in the hydrothermal fluids and hydrothermal minerals in composition, the mean percent content of each component and variation trend. This indicates the direct influence of magma degassing on the hydrothermal fluid. In addition, the contents of volatiles in pumices are rather low and do not support the hydrothermal stripping as the main mechanism to enrich the fluids with gases. The results are consistent with the idea that the direct magma degassing is more important than hydrothermal stripping in supplying gases to the hydrothermal fluids in the Okinawa Trough.  相似文献   

试论与埃达克岩有关的热液矿床成因类型和成矿系列——以中国北方若干矿床为例   总被引：2，自引：0，他引：2  

张炯飞  庞庆邦  朱群  金成洙 《地质与资源》2003,12(3):171-176

中国北方埃达克岩比较发育,有形成于早古生代岛弧环境、中生代中晚期陆弧环境及晚古生代中期和中生代中期大陆板块内环境3种埃达克岩.与形成于岛弧环境埃达克岩相关的热液矿床的成因类型为斑岩型,成矿系列为Cu-Au;与形成于陆弧环境埃达克岩相关的热液矿床的成因类型为斑岩型和浅成低温热液型,成矿系列为Au-Cu-Mo;与形成于板内环境埃达克岩相关的热液矿床的成因类型为斑岩型、夕卡岩和浅成低温热液型,成矿系列为Au-Cu-Pb-Zn.  相似文献   

贵州盘县地区峨眉山玄武岩铜矿的成矿地质条件   总被引：12，自引：0，他引：12  

刘远辉李进  邓克勇 《地质通报》2003,22(9):713-717

以峨眉山玄武岩底部与中二叠统茅口组灰岩接触界面上赋存的黄见坑-哈树富铜矿带为例，论述了这一新类型玄武岩铜矿的成矿地质条件及峨眉山玄武岩浆喷-溢对Cu(Au、Pb、zn、Pt、Pd、Sb、F等)元素的富集和后期热液改造成矿作用，以扩大找矿思路。  相似文献   

新疆西天山莫托沙拉铁(锰)矿床与式可布台铁矿床地质特征对比   总被引：3，自引：0，他引：3       下载免费PDF全文

袁涛 《地质找矿论丛》2003,18(Z1):88-92

新疆西天山富铁矿成矿带位于伊犁板块东端,火山岛弧带弧间断陷盆内.文章详述了莫托沙拉铁(锰)矿床、式可布台铁矿床的地质特征,讨论了矿床成矿机制,对矿床的共性和个性进行了对比.认为铁质来源于海相火山喷气,海解萃取,高密度流体运移,同生断裂提供热液,贮矿盆地下陷接受沉积,最终呈向斜构造.  相似文献   

藏北美多锑矿床容矿硅质岩的地质地球化学特征及成因   总被引：6，自引：1，他引：6       下载免费PDF全文

闫升好  余金杰  赵以辛  徐志忠  王安建  粟登逵 《矿床地质》2003,22(2):149-157

文章通过野外地质调查和系统的岩石学、岩石化学、稀土及微量元素地球化学研究，探讨了藏北美多锑矿床容矿硅质岩的成因和大地构造环境。研究结果表明，美多锑矿容矿硅质岩以致密块状硅质岩为主；主元素化学组成表明，其形成时有大量陆源火山碎屑物质的介入；稀土元素组成及配分模式与热水硅质岩不同，显示其形成于大陆边缘环境；硅质岩和凝灰岩均呈Ba、Sr、P、Ti明显亏损和Nb弱亏损的特点，类似于成熟大陆弧花岗岩。  相似文献   

The Paleoproterozoic McArthur River (HYC) Pb/Zn/Ag deposit of northern Australia: organic geochemistry and ore genesis     

Junhong Chen  Malcolm R. Walter  Graham A. Logan  Mark C. Hinman  Roger E. Summons   《Earth and Planetary Science Letters》2003,210(3-4):467-479

Polycyclic aromatic hydrocarbons (PAHs) in ore and mudstone within the McArthur River ore deposit show compound distribution patterns similar to those of hydrothermally generated petroleum in the Guaymas Basin and significantly different from those found in conventional oil. PAH abundances and their isomer distributions result from a temperature gradient between the source of mineralizing fluids and the sediments fringing the ore system during ore formation. Along with other geochemical, geological, paleobiological and mineralogical lines of evidence, these data provide strong evidence that the ore formed within partially lithified sediments under marine conditions. Given that the McArthur River ore body is an exquisitely preserved example of a sediment-hosted base-metal deposit, these results may be widely applicable. The McArthur deposit is also a rich repository of paleobiological information, allowing studies of the microbiology of ore formation and the paleobiology of an ancient hydrothermal system, as is discussed elsewhere.  相似文献   

Fluxes of fluid and heat from the oceanic crustal reservoir   总被引：1，自引：0，他引：1  

H.Paul Johnson  Matthew J. Pruis 《Earth and Planetary Science Letters》2003,216(4):565-574

Recent discoveries define a global scale fluid reservoir residing within the uppermost igneous oceanic crust, a region of seafloor that is both warm and may harbor a substantial biosphere. This hydrothermal fluid reservoir formed initially within volcanic rocks newly erupted at mid-ocean ridges, but extends to the vastly larger and older ridge flanks. Upper oceanic crust is porous and permeable due to the presence of lava drainbacks, fissuring, and inter-unit voids, and this porosity and permeability allows active fluid circulation to advect measurable quantities of lithospheric heat from the crust to an average age of 65 Myr. A compilation of crustal porosities shows that this fluid reservoir contains nearly 2% of the total volume of global seawater. Heat flow and sediment thickness data allow calculation of reservoir temperatures, predicting 40°C mean temperatures in Cretaceous crust. Utilizing these temperature estimates, heat flow measurements and models for the thermal structure and evolution of the oceanic lithosphere, we have computed mean hydrothermal fluxes into the deep ocean as a function of plate age. The total hydrothermal volume flux into the oceans approaches 20% of the total riverine input and may contribute to the global seawater mass balance.  相似文献