Geochemical Characteristics and Genetic Discussion of the Saersoc Au-Cu Polymetallic Deposits in Southern Margin of Altay Mountains, Xinjiang

Located at the southern margin of Altay mountain syctem, the Sarshoke gold-copper polymetallic deposit is occurred in medium-acidic volcanic-subvolcanic rocks of the upper subgroup of Middle-Aevonian Ashele Group. The wall rocks of this deposit are rhyolite porphyries. The surface and shallow depth are shown by Au-Cu mineralization, while toward the depth, Au-Cu mineralization is gradually weakened and Pb-Zn mineralization is greatly increased, being evidently controlled by stratigraphic horizon. Based on the detailed geological field survey and geochemical comparative study on REE and trace elements of ores, different types of wallrocks, it shows that the REE and trace elements' distribution patterns of Cu and Pb-Zn ores and mineralized rhyolite porphyries are much similar to that of rhyolite porphyries, all of which appears apparently rightward decline, rich in LREE, intensive negative Eu abnormality, enrichment in Ba, U, Zr, Hf and Ti, while decrement in Th, Sr, Sm. Combined with geological characteristics of this deposit, it figures that the Saersoc Au-Cu polymetallic deposit belongs to the type of marine volcanic or subvolcanic hydrothermal deposit, whose Au-Cu and Pb-Zn mineralization is closely related to rhyolite porphyries, which has provide vital sources of metallogenic matter. The dolerite is much unlikely to ores or other types of wallrocks in REE and trace elements distribution patterns, illustrating that the dolerite was possibly result of crystallization and invading of mantle magma from the deep.