青海省锡铁山铅锌矿床沉积盆地构造与找矿方向浅议  

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

作　　者：李正明[1] 王备战 展卫露 战嘉华 郭文波 王宏宇 董星 李增涛 LI Zhengming;WANG Beizhan;ZHAN Weilu;ZHAN Jiahua;GUO Wenbo;WANG Hongyu;DONG Xing;LI Zengtao(Western Mining Co.,Ltd.,Xining 810000,Qinghai,China;Xi’an Northwest Non-ferrous Geophysical and Chemical Exploration Group Co.,Ltd,Xi'an 710068,Shaanxi,China)

机构地区：[1]西部矿业股份有限公司,青海西宁810000 [2]西安西北有色物化探总队有限公司,陕西西安710068

出　　处：《西北地质》2025年第1期166-177,共12页Northwestern Geology

基　　金：西北有色地质矿业集团地质科技项目“复杂条件下深部矿产高分辨电磁探测关键技术研究与工程示范”(XBDKKJ202101)。

摘　　要：锡铁山铅锌矿床位于柴达木盆地北缘,矿体主要产于奥陶系滩间山群O3tna-2正常沉积岩段。对深部构造的探测和原始成矿环境的恢复一直是勘查研究工作的重点。矿山以往深部找矿投入了瞬变电磁法(TEM)和可控源音频大地电磁测深法(CSAMT),对深部的结构、构造反映不够清楚,找矿效果也不理想。2020年首次投入了高分辨广域电磁法(WEFM),取得了较好的勘查效果。笔者结合已有的地质资料,对广域电磁法成果进行综合分析,初步认为锡铁山铅锌矿床原始沉积盆地走向为EW向,属于南高北低的抬斜式盆地。受NE-SW向的斜向推覆作用,形成目前盆地的构造形态;同时推测盆地内部存在两条主要的同生断裂。笔者依据同生断裂和已知矿体的空间位置预测了找矿靶区,指出了锡铁山沉积盆地内铅锌矿的找矿方向。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.

关 键 词：锡铁山铅锌矿 原始沉积盆地 广域电磁法 斜向推覆 找矿方向 

分 类 号：P618.42[天文地球—矿床学] P618.43[天文地球—地质学]