金属硫化物矿石中同沉积组构的成因鉴别

GENETIC IDENTIFICATION OF SYNDEPOSITIONAL FABRICS IN SULFIDE ORES

同沉积组构是特定地质环境的产物,在矿化地层中有一定的空间分布特点。对组构进行成因鉴别时,必须注意野外地质产状的调查。在室内,既要对组构中硫化物颗粒的形态特征、排布形式及其与胶结物的关系进行放大观察,还要对一些可能是多解性的组构形态进一步进行测试研究。电子探针可以对其中的矿物颗粒进行成分对比分析,X光岩组可以测定硫化物晶体的定向特征及其与层理的方位关系。

Syndepositional fabrics seem to be one of the key factors in the identification of the ore deposit origin. For the purpose of determining the exact origin of ore deposits, it is necessary to make genetic identification for some fabrics which look similar to some sediments. The procedure of the identification is as follows: to study metallogenic background and geological features, to find out modes of occurrence and assocations of ore fabrics as well as their spatial distribution in orebodies, to observe microscopic features of the fabrics, to analyse by means of EMP chemical composition and variation of major sulfides in different laminae, and to determine with X-ray analysis crystallographic orientation relative to the orientation of the bedding.