张瀚夫 田艳丽 丛明磊

摘要：索纳嘎银铅锌矿床成因类型为中低温热液矿床，矿体赋存于早白垩世斑状细粒花岗岩体与下侏罗统红旗组地层接触带。主矿体1条，即1号矿体。矿体受NEE走向平行裂隙控制，矿化类型为交代——充填型。矿体切穿红旗组地层和斑状细粒花岗岩体，倾角较陡。矿体呈脉状、透镜状，走向NEE，倾向北西，倾角45°～70°，矿体向南西方向侧伏，侧伏角55°。矿化富集规律为：岩体接触带凹陷部位矿化富集，控矿裂隙延走向凹陷部位矿化富集，控矿裂隙倾角由缓变陡的部位矿化富集。根据矿体产状规律及矿化富集特征推测，矿区西南方向（8线以西）深部（海拔400米以下）是深部找矿的有利地段。

关键词：内蒙古东乌旗；索纳嘎；银铅锌矿床；矿体产状特征；矿化富集规律；成矿预测

Abstract： The Suo Naga Silver-lead-zinc deposit is medium or low temperature hydrothermal deposit. The ore-body occurred in the contact zone of porphyritic fine-grained granite in early cretaceous and Hongqi Formation of lower Jurassic. No.1 ore-body is the main ore-body. Its controlled by a parallel crack with NEE55°±strike， and its mineralization type is metasomatic-filled type. The ore-body cut through the stratum of Hongqi Formation and porphyritic fine-grained granite. The dip angle is a little high. The ore-body presents with vein and lenticular mode， NEE strike， north-west dip， dip angle between 45°and 70°。 The ore-body lateral-trend is south-west， and pitch is 55°. There are such places which are mineralized enrichment： the depressed part of contact zone between lithosomes； the depressed part of ore-controlling crack extending the strike； dip angle of ore-controlling from slight to steep. It can make a conjecture from the attitude of ore-body and the characters of mineralized enrichment. The south-west of mining area（the west of line 8， blow the altitude of 400 meters） is the preferable deep ore-finding area.

Key Words： Dong WUqi of Inner Mongolia， Suo Naga， Silver-lead-zinc deposit， the characters of the attitude of orebody， rules of mineralized enrichment， Metallogenic prognosis

1. 大地构造位置

索纳嘎银铅锌矿床位于内蒙古自治区东乌珠穆沁旗境内。大地构造位于兴安地槽褶皱系，东乌珠穆沁旗早华力西地槽褶皱带（图1）。区内构造运动频繁，褶皱断裂构造均较发育。受大地构造的控制和影响，构造线主要表现为北东向和北北东向展布的特点。侵入岩较为发育，出露面积较大，构成区内北北东及北东向隆起带的主体。岩石类型简单，以酸性侵入岩为主，其次为中酸性的小型侵入体。

2. 矿区地质特征

2.1 地层

矿区出露地层较为简单，主要为下侏罗统红旗组细砂岩、粉砂岩及泥质粉砂岩，新近系宝格达乌拉组红粘土，第四系全新统冲积砂土、坡洪积物（图2）。……