在岩溶型铅锌矿床形成过程中有机质的地球化学行为

在岩溶及其伴生的成矿作用发生的同时,来自溶解岩石中被分离出的有机质、地表水携带的陆生植物及由含矿卤水自深部或它地搬运的有机化合物与其它岩溶液填物一起沉积于岩溶洞穴中.根据它们的不同来源及受到岩溶成矿的影响程度,可区别出改造型、继承型、搬迁型、原生型有机质.由于有机质的热稳定性低,因此能较好地反映岩溶的性质、演变过程及其中成矿的特点.研究岩溶型铅锌矿床中有机质的类型、变化、分布规律,有助于矿床成因研究,指导找矿.     

四川银矿床地质特征、分布规律及找矿方向

四川银矿床有6种类型,除少数为独立银矿外.多数属与铜、铅锌、金的共生矿床;在区域分布上.集中于古隆起边缘坳陷带上,具水平分带;成矿高峰有晋宁、燕山两期.今后须拓宽找矿思路,寻找新的含矿层位和新的矿床类型.     

任意测站法测设曲线

在公路施工中，曲线的测设是经常发生的。偏角法、切线支距法，是曲线测设的常用方法，但在放样城市交叉路喇叭口及盘山道路时，却要多次搬动仪器，给工作带来很大的不便。在高速公路施工中，往往因放样精度较差也带来一些麻烦。笔者在约旦王国阿布努赛新城建设中，使用任意测站法极坐标放样曲线，节约人力（一般只需2—3人），加快了速度，保证了精度，取得了较好的效果。     

Exhalites Associated with Pb-Zn Mineralization in Devonian System and Their Prospecting Implications,Qinling,China

The exhalation origin of the ankerite-siliceous rocks associated with Pb-Zn mineralizations in the Devonian system of Qinling is discussed in the light of geologic setting,sedimentary-tectonic environment,lithological and chemical characteristics.On this basis,criteria for distinguishing them and their potential role as an indicator in prospecting are described.Ankerite-siliceous rocks are developed in the strata-bound Pb-Zn polymetallic belt in the Devonian system of Qinling.They are microcrystalline,dark grey and compact in appearance and are commonly carbonaceous,As a persistent ore-bearing horizon in the region,their genetic relation to the Pb-Zn deposits in generally accepted.However,a consensus has yet to be reached among geologists concerning their origein as a product of hydrothermal metasomtism at the late stage of sedimentation or as exhalite resulting from submarine exhalation.Accumulating evidence from direct observations on modern submarine hydrothermal systems strongly indicates that seafloor exhalation is a much more common geologic process than previously thought nd its metallogenic implications have long been overlooked.Characteristics of the ankerite-siliceous rocks as a product of exhalation and their significance as a guide in prospecting are described on the basis or geological setting,lithology,lithochemistry,REE,and isotopic and trace element features.     

福建上蔡硫－多金属矿区前峰西矿段银的矿床地球化学特征及赋存状态研究

福建上蔡硫－多金属矿区前峰西矿段矿床中银的地球化学背景值普遍偏高，局部富集，从矿石矿相鉴定，扫描电镜分析中得知银是以独立矿物年银矿形式赋存于方铅矿中的．首先由各种藻类生物从海水中摄取Ｓ，Ｆｅ，Ｃｕ，Ｐｂ，Ｚｎ，Ａｇ，Ｔｅ等元素的离子，于成岩成矿阶段形成多种金属矿物。由于Ａｇ，Ｔｅ，Ｐｂ地球化学性质、晶体化学性质相近，Ｔｅ，Ａｇ以类质同象状态进入方铅矿。区域变质－矽卡岩化过程中Ａｇ，Ｔｅ在方铅矿中，也随之结合成Ａｇ２Ｔｅ（碲银矿）熔离出来成为方铅矿的不混熔包体或次生包体。