金龙山-丘岭卡林型锑金矿床稀土元素地球化学     

张复新  马建秦 《地质与勘探》1999,35(6)

金龙山—丘岭卡林型Sb—Au矿床的形成受沉积建造和岩相、剪切变形构造、后生成矿作用3种因素的控制,矿床属沉积—改造成因类型。根据REE含量、组成和特征参数,即REE、Ce/Y、(La/Sm)N、(La/Yb)N、δEu、δCe,探讨了该矿床的稀土元素地球化学及它与金龙山—丘岭矿床形成和演化的关系。  相似文献   

Sediment type distribution in reservoirs: sediment source versus morphometry     

J. Abraham  P. M. Allen  J. A. Dunbar  S. I. Dworkin 《Environmental Geology》1999,38(2):101-110

 Bottom sediments were collected from seven Texas reservoirs to assess the spatial distribution of sediment types in reservoirs. The sediment samples were analyzed for water content, organic content, and grain-size distributions. The reservoirs are characterized by distinct water content patterns (referred to in this paper as Types I, II, and III) that reflect the lithologic units comprising their drainage area. The water content, organic content, and percent mud decreases from Type I (shale, marl) through Type II (limestone-marl-sandstone) to Type III (granite-gneiss-schist-sandstone) reservoirs. Reported elemental concentrations in the reservoir sediments are consistent with concentrations in the dominant rocks within their drainage area. While water depth accounts for part of the spatial distribution, sediment source explains the overall distribution of sediment types. Coarse-grained source rocks, multiple source rocks, and multiple tributaries which input sediment at different points contribute to an inconsistent sediment type distribution. Depending on the sediment source, sand and gravel-size sediments are present in the deeper regions of some reservoirs. This disrupts the classical morphometry (water depth, slope) controlled sediment distribution pattern (coarser sediments in shallower regions and finer sediments in deeper regions) of natural lakes. Thus, the location of tributaries and the type of sediments they carry are the dominant factors that control the sediment type distribution in reservoirs. Received: 16 June 1998 · Accepted: 24 August 1998  相似文献   

Polymetallic Mineralization at the Shin-Ohtoyo Deposit, Harukayama District, Hokkaido, Japan     

Akira IMAI  Hiroharu MATSUEDA    Ryoichi YAMADA  Kenzo MASUTA 《Resource Geology》1999,49(2):75-88

Abstract: The Shin-Ohtoyo Cu–Au deposit is located in the Harukayama district, 20 km west of Sapporo, Hokkaido, Japan. Both acid-type disseminated and adularia–quartz–type vein Au mineralizations have been recognized within a small distance of less than 500 m in the district. Mineralogical characteristics of sulfide ores from the Shin-Ohtoyo deposit have been proved to be polymetallic. Ore minerals containing Sn, V, Bi and Te are recognized. Nine ore types are recognized in terms of characteristic mineral assemblage; (1) chalcedonic quartz veinlets in silicified zone around the deposit, (2) bismuthinite, emplectite, friedrichite and tetrahedrite, (3) an unnamed Cu–Sn–Fe–Zn sulfide, colusite-series minerals, stannoidite, emplectite and tetrahedrite, (4) bournonite, Se-bearing galena and tetrahedrite, (5) luzonite/famatinite and Ag-bearing tetrahedrite, (6) colusite-series minerals, emplectite, aikinite and tetrahedrite/goldfieldite, (7) luzonite/famatinite, colusite-series minerals, mawsonite and tetra–hedrite/goldfieldite, (8) enargite, luzonite/famatinite and tetrahedrite, and (9) colusite-series minerals and tetrahedrite. The first occurrence of friedrichite and stibiocolusite from Japan are reported. The chemical formula of the unnamed phase corresponds to Cu₆(Cu, Fe, Zn)Sn₃S₁₀. Sulfur isotopic ratios (δ³⁴S) of sulfides from the stockpile range from –0. 5% to +1. 9%, and those from drill cores recovered by Metal Mining Agency of Japan (MMAJ) vary from –2. 7% to +0. 8%. Sulfur isotopic ratio of barite in a cavity in the silicified tuff breccia collected from the stock pile yields +27. 1%, while that of barite collected from MMAJ core is +21. 7%. Sulfur isotopic thermometry applied for a pair of barite (+21. 7%) and associated pyrite (+1. 8%) indicates about 300°C. High–Te tetrahedrite composition from both the chalcedonic quartz vein in the silicified zone around the Shin-Ohtoyo deposit and the polymetallic sulfide ores from the adit of the deposit, suggests that the Au mineralization in the former is attributed to a hydrothermal system marginal to the polymetallic mineralization.  相似文献   

德令哈中生代沉积盆地成因类型及其与南祁连造山带的关系   总被引：3，自引：0，他引：3  

杨明慧 《西北地质科学》1999,20(1):15-22

长期以来,对柴达木盆地中生代的大地构造属性一直存在争议．笔者根据柴达木盆地北缘的德令哈盆地中生代盆地充填序列、基底沉降过程和大地构造相分析结果认为,该盆地具有典型的前陆盆地沉积－构造演化特点．（１）二叠（？）一中三叠世发育类复理石盆地组合和早侏罗一早白垩世发育陆相含煤磨拉石盆地组合,构成前陆盆地的“标型”充填;（２）上凸的总沉降曲线反映前陆盆地的发育规律;（３）德令哈前陆盆地的形成说明柴达木板块和华北板块的末次陆一陆碰撞发生在晚三叠世,早侏罗－早白垩世的构造运动则归属于南祁连对柴达木板块的陆内逆冲推覆作用．  相似文献   

深基坑边坡支护方式的现状     

戴长冰  水丽 《世界地质》1999,18(4):73-77

根据目前国内边坡支护工作中的主要方式,将深基坑边坡支护按其结构的受力状态和支护的作用原理进行分类,详细论述了各种深基坑边坡支护方式的机制和适用条件,对今后岩土工程的实际工作具有一定的参考作用。  相似文献   

造山带区域地层学研究的几个问题   总被引：7，自引：0，他引：7  

冯庆来 《地学前缘》1999,6(3):133-138

根据地层层序保存程度,将造山带地层划分为史密斯地层、有限史密斯地层和非史密斯地层3种类型。有限史密斯地层是造山带地层的主要类型,它由不同时代、不同成因的构造地层断片组成,史密斯地层层序律仅适用于地层断片内部地层层序研究。文中认为有限史密斯地层的层序是可以恢复的,并提出了恢复方法和技术路线。最后,以活动论、单元论和阶段论为指导,论述了造山带地层系统研究的理论模型。  相似文献   

论全球性中-新生代陆内造山作用与造山带   总被引：29，自引：4，他引：25  

崔盛芹 《地学前缘》1999,6(4):283-293

对不同类型造山作用与造山带的深入剖析,在现代地学研究中占有重要的位置。迄今对造山带类型划分以及陆内（ 板内） 造山带是否存在及其形成机制问题,尚有不同认识。文章在阐明造山带分类准则的基础上,将全球性中－ 新生代造山带划分为陆缘型、陆间型与陆内型三大类。对陆内造山带则划分出发育在前寒武纪古克拉通基础上、发育在前中生代陆缘、陆间造山带基础上两种类型。文内还对全球性中－ 新生代陆内造山作用与造山带的展布特点、形成机制及其大陆动力学意义进行概括论述  相似文献   

金矿床复式矿化类型与动力学   总被引：2，自引：0，他引：2  

关连绪  韩先菊 《地球学报》1999,20(4):402-408

根据研究提出矿化迭代及其与矿化叠加的区别。金矿化分为基本矿化类型和复式矿化类型两大类,后者分为3类9亚类。最后论述了矿化类型的构造动力学和流体动力学。  相似文献   

试论钾盐矿床的成矿条件   总被引：17，自引：0，他引：17  

魏东岩 《化工矿产地质》1999,21(1):1-6,14

钾盐是钾肥的主要原料。钾盐矿床一直是我国地质找矿的重点。世界钾盐矿床研究表明,钾盐矿床比其它盐类矿床需要更为“苛刻”的成矿条件,表现在大地构造条件、岩相古地理条件、气候条件、生物化学沉积条件、物源条件、干盐湖条件等。研究并总结世界钾盐矿床成矿条件,对在中国进一步找寻钾盐矿床具有重要的借鉴意义。  相似文献   

岩湾矿段风化磷矿形成条件及其三种类型     

陈拥军 《化工矿产地质》1999,21(4):225-230

湖北省鹤峰磷矿走马矿区岩湾矿段风化磷矿是湖北境内首次探明的一中型风化磷矿。矿床成因类型有风化残余型、风化淋滤型、洪积型砂磷矿等三类。在时间上 ,风化淋积型矿体位于风化残余型矿体之下 ,是风化残余型的继承发展。在雨水和洪水冲刷下 ,风化残余磷矿在适当的低洼地带堆积成洪积型砂磷矿。对这种风化矿的勘探应因地制宜 ,灵活运用。对岩湾矿段风化磷矿的成因探讨和勘探研究为东山峰寻找和勘探类似风化磷矿积累了经验。  相似文献