华南两类花岗岩型铀矿床的地球化学识别标志及成因研究     

章邦桐 《华东地质学院学报》1992,15(2):119-124

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方格法采样在金矿床和铅锌多金属矿床中的应用     

徐邦金 《湖南地质》1992,11(3):239-243

在地质普查勘探工作中,合理地选择采样方法,能提高地质找矿效果,加快找矿进程。通常应用的采样方法是刻槽法,笔者结合已勘探的金矿床、铅锌多金属矿床的实际情况,在不同矿区中进行了不同采样方法研究试验,试验结果证明l0×10cm规格的方格法是一种应用广泛,代表性强,效益好的采样方法。  相似文献   

宝玉石的找矿标志   总被引：1，自引：0，他引：1  

赖祥政 《矿物岩石》1992,12(1):115-118

本文主要探讨宝石的找矿标志。包括在超基性岩、辉长岩—斜长岩中含虹彩长石、喷发岩、花岗伟晶岩中的宝石,还有变花岗岩云英岩中含海蓝宝石,镁矽卡岩中含尖晶石、红宝石、蓝宝石和青金石,风化壳中的宝石,砂矿中的宝石等。  相似文献   

通化石家铺子金矿床地质特征及成因探讨     

陈春福 《吉林地质》1990,9(1):21-30

金矿床产于中元古界老岭群珍珠门组中,受北东向头道—金厂—通化断裂的次一级F_(210)断裂控制。矿石类型主要为褐铁矿型矿石及黄铁矿型矿石。金与黄铁矿关系密切,主要呈自然金出现。金来源于含金较高的珍珠门组第三段地层岩浆期后的矿液中。成因为岩浆期后热液迭加改造的层控破碎带蚀变岩型金矿床。  相似文献   

论湖南省泥盆系层控矿床的分类     

王甫仁  匡耀求 《湖南地质》1990,9(1):28-34

本文就不同学者所提出的层控矿床分类方案进行了综合评述,论述了作者们近年来研究湖南省泥盆系层控矿床提出的一种新的分类方案,将其分为沉积—改造型(简称改造型)、后成渗滤热液型(简称渗滤型)和岩浆热液叠加型(简称叠加型)三大类;然后根据矿种及成矿元素组合分成若干类,再根据矿体形态及矿体与赋矿地层的整合关系分成若干小类。并就湖南省泥盆系内产出的矿床作了具体划分,总结了各类矿床的特点与区分标志。改造型矿床主要是黄铁矿床,矿质来自泥盆系,成矿受沉积相和同沉积断裂控制,渗滤型矿床主要为铅锌、锑、金矿床,矿质来自下伏岩层,成矿受成岩后长期活动断裂控制,叠加型矿床主要为钨、铅锌、磁黄铁矿等矿床,矿质主要来自燕山期岩体,成矿受燕山期断裂和岩浆作用控制。该分类对指导层控矿床的找矿勘探具有重要意义。  相似文献   

东坡矿田构造层次与内生成矿作用及其隐伏矿床预测     

黄柏 《湖南地质》1990,9(3):13-19

在矿床地质研究程度极高的郴县东坡矿田,近几年相继发现了野鸡尾石英斑岩型锡矿床和红旗岭锡矿床等,这表明该矿田仍有找矿潜力。根据我们对东坡矿田构造层次与成矿关系等的研究发现,东坡矿田的内生多金属矿床均产出在构造层次发生梯变地带(段),从而提出从构造层次的角度预测隐伏内生矿床的四条基本原则,并在东坡矿田提出了东坡山、横山岭、龙头岭三个隐伏矿床预测区。因此矿田构造层次的研究是矿田控岩控矿构造研究的一个新领域,对成矿预测具有重要意义。  相似文献   

试论层状铜矿的三种主要成因模式   总被引：8，自引：0，他引：8  

华仁民 《地质论评》1995,41(2):112-120

层状铜矿是铜矿资源中仅次于斑岩铜矿的重要矿床类型,包含多种成因机制,历来有同生与后生之争。本文归纳了这类铜矿的３种成因模式,即“沉积－成岩”、“沉积－喷气”和“沉积－改造”模式,讨论了它们的不同特征和机制,以及三者之间的相互关系。文中对“沉积－改造”模式进行了重点讨论,并强调了这一成矿作用的意义。  相似文献   

Sulfur redox reactions: Hydrocarbons,native sulfur,Mississippi Valley-type deposits,and sulfuric acid karst in the Delaware Basin,New Mexico and Texas     

C. Hill 《Environmental Geology》1995,25(1):16-23

Hydrocarbons, native sulfur, Mississippi Valley-type (MVT) deposits, and sulfuric acid karst in the Delaware Basin, southeastern New Mexico, and west Texas, USA, are all genetically related through a series of sulfur redox reactions. The relationship began with hydrocarbons in the basin that reacted with sulfate ions from evaporite rock to produce isotopically light ( ³⁴S = -22 to -12) H₂S and bioepigenetic limestone (castiles). This light H₂S was then oxidized at the redox interface to produce economic native sulfur deposits ( ³⁴S = -15 to +9) in the castiles, paleokarst, and along graben-boundary faults. This isotopically light H₂S also migrated from the basin into its margins to accumulate in structural (anticlinal) and stratigraphic (Yates siltstone) traps, where it formed MVT deposits within the zone of reduction ( ³⁴S = -15 to +7). Later in time, in th zone of oxidation, this H₂S reacted with oxygenated water to produce sulfuric acid, which dissolved the caves (e.g., Carlsbad Cavern and Lechuguilla Cave, Guadalupe Mountains). Massive gypsum blocks on the floors of the caves ( ³⁴S = -25 to +4) were formed as a result of this reaction. The H₂S also produced istopically light cave sulfur ( ³⁴S = -24 to -15), which is now slowly oxidizing to gypsum in the presence of vadose drip water.  相似文献   

Deciphering some unique paleotemperature indicators in halite-bearing saline lake deposits from Death Valley, California, USA     

Sheila M. Roberts  Ronald J. Spencer  Wenbo Yang  H. Roy Krouse 《Journal of Paleolimnology》1997,17(1):101-130

Saline lake deposits are arguably the best source of mid- to low-latitude terrestrial paleoclimate data. Alternating clastic sediments and evaporites of different chemical composition have long been recognized as sensitive records of changes in inflow and aridity related to a variety of climate parameters. Several sources of paleotemperature information from a halite-bearing saline lake deposit are described here – pseudomorphs of a cold-temperature evaporite mineral, homogenization temperatures of fluid inclusions in halite, and stable-isotope compositions of fluid inclusions in halite. Examples of these paleoclimate data come from analysis of the lower half of a 185-m core drilled in Pleistocene saline lake deposits at Death Valley, California. Daily and seasonal temperature variations in saline lake waters create conditions for the appearance and disappearance of temperature-dependent mineral phases. In the Death Valley core, hexagonal-shaped halite crystals, probable pseudomorphs of the cold-temperature hydrous mineral, hydrohalite (NaCl2H₂O), provide evidence of brine temperatures below about 0 °C. Homogenization temperatures of fluid inclusions in primary halite offer an actual (not proxy) record of surface-brine temperatures. Samples with primary fluid-inclusion textures are carefully selected and handled, and data are collected from single-phase aqueous-brine inclusions chilled to nucleate vapor bubbles. Temperature variations are observable at scales of individual halite crystals (hours to days), single halite beds (weeks to months or years), and multiples of beds to entire facies (hundreds to tens of thousands of years). A ¹⁸O/D stable isotope record from the minute quantities of brines in fluid inclusions in halite is accessible using a method recently developed at the University of Calgary. The stable isotope record from the Death Valley core, a complex response to climate variables including temperature, humidity, storm patterns or seasons, and inflow sources, compliments and expands the interpretation emerging from the stratigraphy and homogenization temperatures.  相似文献   

我国与寻找超大型矿床有关的基础研究进展   总被引：8，自引：0，他引：8  

赵振华  刘秉光  李朝阳 《地球科学进展》2001,16(2):184-188

我国于1992年将超大型矿床基础性研究列入国家基础研究重大项目，已取得如下成果：确定了超大型矿床的定义和分类原则，发现了超大型矿床在矿化类型上的选择性和局限性，我国超大型矿床主要分布于克拉通边缘，铅同位素的地球化学急变带，地壳厚度急变带，碳酸岩系向碎屑岩系过渡带是超大型矿床产出的有利宏观背景；立足于寻找超大型矿床，提出了6个新的成矿域；确定了我国东部喜山期和南方晋宁期对金属成矿的重要意义。此外，还对邻国超大型矿床成矿带和成矿类型向我国延伸的可能性以及超大型矿床与矿床密集区时空展布及成因上的复杂性进行了研究，提出了独立银矿床及成矿带概念，对我国当前开展的超大型矿床基础研究作了概要介绍，简要评述了当今国际上超大型矿床研究趋势。  相似文献