桂北四堡群地层地球化学研究

STRATIGRAPHIC GEOCHEMICAL STUDIES OF SIBAO GROUP IN NORTH GUANGXI

桂北四堡群作为一套下中元古界火山－沉积建造，具有一系列地球化学特点：金含量呈多峰分布，平均金丰度较低，金与其它元素的相关性较弱；Ｓｎ、Ｃｕ、Ｎｉ、Ａｕ、Ａｇ、Ａｓ、Ｓｂ等元素变异系数大，属活动性强的元素，其中Ｓｎ、Ｃｕ、Ｎｉ与基性一超基性岩有关，而Ａｕ、Ａｇ、Ａｓ、Ｓｂ主要与沉积变质岩相联系；四堡群微量元素组合以亲铁和亲铜元素为特征。结合桂北四堡群锡多金属矿化和金矿化的发育，作者认为桂北四堡群可能是Ｓｎ－Ｃｕ－Ｎｉ－Ａｕ－Ａｇ－Ａｓ－Ｓｂ组合综合性原始含矿建造。

As Pt1-2 volcano-sedimentary formation, Sibao Group in North Guangxi has a series of geochemical characteristics: The distribution of gold is multiple kurtosis, the average content of gold is lower and the correlation of gold with other trace elements is poor. Sn, Cu, Ni, Au, Ag, As and Sb have high variation coefficients and strong mobilities, in which Sn, Cu and Ni are related to basic-ultrabasic rocks and Au, Ag, As and Sb to sedimentary-metamorphous rocks. The associations of trace elements are characterized by siderophile elements and chalcophile elements. Based on the above and the development of tin polymetallization and gold mineralization,the paper thinks that Sibao Group is probable synthetical protogenous ore-bearing formation of Sn-Cu-Ni-Au-Ag-As-Sb association.