内蒙古二道河子铅锌矿床构造控矿作用及找矿方向

李兴++刘云华++关强兵刘方杰李欢+尚志辉

文章编号：16726561（2016）06079112

陕西 西安710075； 3西南能矿集团股份有限公司，贵州 贵阳550004）

摘要：内蒙古二道河子铅锌矿床位于大兴安岭得尔布干多金属成矿带。通过详细的野外地质调查，矿区发育有NE、NW、近SN向等3组断裂构造。矿体主要呈脉状—网脉状产出于NW向断裂构造带中，断层面平直，延伸稳定。矿体与围岩界线明显，矿石结构完整。矿化围岩主要为流纹质岩屑晶屑凝灰岩；NE向次级断层内充填梳状石英脉，矿化较弱，截断NW向矿体但位移距离不大；SN向断层挫距较大，对矿床起一定的破坏作用。矿区发育的NE、NW向构造为成矿期前或成矿期得尔布干断裂的次级断裂构造，NW向构造早期具有压剪性构造特征，成矿期为张性环境，成矿期后封闭；NE向断裂在成矿期为挤压环境，成矿期后有继承性活动；SN向断裂为成矿期后构造。围岩岩性对成矿具有重要的控制作用。结合物探与化探异常特征，矿区西北部偏酸性岩石分布范围内的NW、NE向构造交汇部位是寻找厚大富集型矿体的最有利靶区，深部岩性不整合面及火山穹窿可能是寻找似层状矿体的有利位置。

关键词：铅锌矿床；控矿构造；找矿方向；岩浆热液；岩屑晶屑凝灰岩；得尔布干断裂；内蒙古

中图分类号：P613；P618.4文献标志码：A

Tectonic Orecontrolling and Prospecting Direction of Erdaohezi PbZn Deposit in Inner Mongolia

LI Xing1， LIU Yunhua1， GUAN Qiangbing2， LIU Fangjie2， LI Huan1， SHANG Zhihui3

（1. School of Earth Science and Resources， Changan University， Xian 710054， Shaanxi， China；

2.Shaanxi Nonferrous Metals Holding Group Co.， Ltd.， Xian 710075，Shaanxi， China；

3. Southwest Energy and Mineral Resources Corporation Co.， Ltd.， Guiyang 550004， Guizhou， China

）

Abstract： Located in the northwest of Derbugan fault， the Erdaohezi PbZn deposit belongs to Derbugan metallogenic belt in Great Xingan Range. Through the detailed field geological survey，NE， NW， nearly SNtrending fault systems develop in Erdaohezi mining area. The orebodies are controlled by NWtrending faults， which have flat fault plane and stable extension， with mainly veinstockwork type. The lines between orebodies and wallrocks are obvious， and the ore textures are integrated. The orehosting rocks are mainly rhyolitic lithic crystal tuff. NEtrending secondary faults are filled with a lot of combtype quartz， and the mineralization is weak； they crosscut the NWtrending orebodies with little displacement； SNtrending faults break the deposits because of the bigger displacement. NE and NWtrending structures are the secondary faults of Derbugan fault before and during the metallogenic period； NWtrending structures are pressure shear in the early period， and tensional environment during the metallogenic period， and closed after the metallogenic period； NEtrending faults are compressional environment during the metallogenic period， and have successive activity after the metallogenic period； SNtrending faults form after the metallogenic period. The lithology of hostrock is an important control factor for metallogenesis. Combined with the characteristics of geophysical and geochemical anomalies， the overprinting zones of NE and NWtrending structures with intermediatefelsic volcanic rocks in the northwest of Erdaohezi mining area are the most favorable targets for prospecting large industrial orebodies， and some heterolithic unconformity interfaces and volcanic domes are the vantage points for finding stratiformlike orebodies.

Key words： PbZn deposit； orecontrolling structure； prospecting direction； magmatic hydrothermal liquid； lithic crystal tuff； Derbugan fault； Inner Mongolia

0引言

二道河子铅锌矿床位于内蒙古自治区根河市得耳布尔镇和海拉尔—根河中生代火山盆地北西缘，属得尔布干成矿带。该成矿带已发现有得耳布尔铅锌矿、比利亚谷铅锌银矿、东珺铅锌银矿等大中型矿床及一大批矿点、矿化点，显示出该区具有较大的铅锌矿床找矿潜力。……