摘要
放牛沟矿床主要成矿元素Zn、Pb并非由地层提供,而是来自岩体深部,通过岩体接触带构造向火山—沉积岩系运移而形成矿床及原生异常的。Zn、Pb、Cu、Ag等元素正异常与Cr、Sr等元素负异常的套合产出是矿床存在的重要标志.矿体、矿组、矿床异常有明显的分带规律,分带性指数从浅部到深部呈规律性变化.根据Ag/Bi可判别前缘、尾晕,利用PbZnAgBa/CuBi可判别矿组和矿床原生异常的剥蚀程度.
Fangniugou ore deposit locates in the contact zone between granite (*41) and Shifeng formation of upper Ordovician series (O3S2). Regional concentration of Zn and Pb is lower than or similar to the Clark value. Therefore, it is believed that the ore-forming materials are not derived from the stratum.The positive anomalies of Zn, Pb, Cu and Ag coexisting with the negative anomalies of Cr and Sr is an important indicator of ore deposit , Zoning of primary anomaly in ore bodies , ore body groups and ore deposit are clearly recognized. Front halo and rear halo can be distinguished by Ag/Bi. The denudation level of primary anomalies of ore body groups and ore deposit can be judged by Pb Zn Ag Ba /Cu 81. Several primary anomalies are evaluated on the basis of the indiators and parameters. Finaly, the forming process of the primary geochemical anomaly has been discussed.
关键词
硫铁矿
多金属矿
矿床
地球化学
primary geochemical anomaly, geochemical zoning, parameters and indicators for geochemical exploration
