庐枞盆地及其周缘中三叠世黄马青组含铜岩石类型及特征

Copper-bearing rock types and features of the mid-Triassic Huangmaqing Formation in the Lu-Zong basin and the periphery

庐枞盆地及其周缘黄马青组系三角洲前缘相沉积,主要含铜岩系由泥岩—砂岩岩组组成,其中主要含铜岩石类型包括:灰绿色、深灰、灰黑、紫黑色等还原色调的粉砂质泥岩或泥质粉砂岩等细颗粒岩类,铜元素含量100×10-6～3600×10-6之间,平均达1051.8×10-6,Ag与Cu具有正相关性。金属矿物以辉铜矿为主,少量黄铜矿,呈星点状分布于岩石微层理中,是在分流间湾还原环境下形成。

The Huangmaqing Formation in the Lu-Zong basin and the periphery is of delta front facies sediments and its main copper-bearing rock series consist of mudstone-sandstone petrofabric, of which the dominant rocks are greyish green, dark grey, greyish black and purplish black silty mudstones or muddy siltstones, i.e., fine-grained rocks of reduced color, with copper content of 100×10^6 to 3600×10^-6, 1051.8× 10^-6 in average. Ag is positively correlated with Cu in content. Metallic minerals include major chalcocite and minor chalcopyrite, which sporadically occur in micro-beddings of rocks as a product formed in interdistributory bay, a reduced environment.