法国比利牛斯山Trimouns滑石-绿泥石矿床地质与成因

位于法国比利牛斯山的Trimouns矿床是世界上最大的滑石-绿泥石矿床之一。对该矿床形成的条件及滑石和绿泥石矿石的含量已较清楚。它是由不同类型的岩石通过热液交代蚀变而形成的，主要包括白云岩蚀变为滑石为主的矿石和硅铝质岩石(云母片岩和伟晶岩)蚀变为绿泥石为主的矿石。滑石矿石显示片理化结构(滑石片岩)或压实块状结构(块滑石)。由伟晶岩蚀变而来的绿泥石矿石为呈绿色的球状矿体，而由云母片岩蚀变而来的绿泥石矿石呈块状或片理状、颜色为灰绿色和深灰色。本文对欧洲这个独一无二的滑石和绿泥石矿床的地质特征和成因进行了总结和讨论。流体包裹体研究表明成矿流体为高盐度(20to30％eq．wt％NaCl)、中温(320℃)、压为为2．5kbars。磷钇矿和独居石的U—Ph定年结果表明，成矿年代为112—97Ma，成矿作用可能持续了16Ma以上。

Geology and oregenesis of the Trimouns talc-chlorite ore deposit, Pyrénées, France

The Trimouns deposit, in the French Pyr閚閑s, is one of the largest talc and chlorite exploitation in the world. The conditions of formation and concentration for talc and chlorite ores are now well known. The deposit consists the metasomatic alteration of various rocks, mainly dolostones altered into talc-dominant ore and silico-aluminous rocks (mica schists and pegmatites) into chlorite-dominant ore. The talc ore shows schisteous texture (talc schist) or in compact mass (steatite). The chlorite ore altered from pegmatite show green colors and ball bodies. The chlorite ores altered from mica schists are either massive or schisteous ores with graygreenish and dark gray colors. This paper summarizes the general geology and ore genesis of this exceptional talc and chlorite ore deposit in Europe. Fluid inclusion study shows high salinity of 20 to 30% eq. wt% NaCl, intermediate temperature of 320℃ and pressure of 2.5 kbars for the formation of Trimouns deposit. According to U-Pb dating on xenotime and monazite, the mineralization took place during 112 to 97 Ma and last for at least 16 million years.