Discussion on Structure and Prospecting Direction of Xitieshan Lead-zinc Deposit Sedimentary Basin in Qinghai Province

Xitieshan lead-zinc deposit is located in the northern margin of Qaidam Basin, and the ore body is mainly produced in the normal sedimentary rock section of O3tna-2 of the Ordovician Tanjianshan Group. The exploration of deep structures and the restoration of the original metallogenic environment have always been the focus of exploration and research work. In the past, transient electromagnetic method (TEM) and controlled source audio frequency magnetotelluric sounding (CSAMT) were used in deep prospecting of the mine, which did not reflect the deep structure and structure clearly enough, and the prospecting effect was not ideal. In 2020, the high-resolution wide area electromagnetic method (WEFM) was put into use for the first time, and good exploration results were achieved. Based on the existing geological data and the comprehensive analysis of the results of the wide area electromagnetic method, this paper preliminarily believes that the original sedimentary basin of the Xitieshan lead-zinc deposit is oriented in the east-west direction and belongs to an uplifted basin with the south high and the north low. Due to the NE - SW oblique nappe, the current structural form of the basin was formed; At the same time, it is speculated that there are two main contemporaneous faults in the basin. Based on the syngenetic faults and the spatial location of known ore bodies, this paper predicts the prospecting target area and points out the prospecting direction of lead-zinc deposits in the Xitieshan sedimentary basin.