吉林海沟金矿的构造应力场分析与变形期次  

Analysis on structural stress field and deformation stages in Haigou gold deposit of Jilin

作　　者：汪建宇[1] 刘志宏[2] 李绪俊[2] 周飞[2] 任德奎[1] 赵呈祥 赵乘乘[2] 刘桓[2] 白江涛[1] 孙石磊[1] 任山峰[1] 

机构地区：[1]吉林海沟黄金矿业有限责任公司,吉林安图133600 [2]吉林大学地球科学学院,长春130061 [3]青海省地质矿产勘查开发局,西宁810001

出　　处：《世界地质》2011年第4期593-599,共7页World Geology

基　　金：中国地质调查局项目(资[2010]矿评01-20-05);国家自然科学基金项目(41072150);吉林省科技发展计划项目(20090479)联合资助

摘　　要：对海沟金矿的断层、节理进行野外和井下研究,应用赤平投影方法对节理产状进行统计与分析,确定研究区节理有6个较为明显的优势产状,构成3个节理系,并进一步确定了3期变形作用的构造应力场。海沟金矿早期受到NW--SE向伸展作用影响,使先存的近EW向海沟断层发生左行走向滑移,在海沟断层上盘形成NE向正断层组合,同时伴有含金石英脉的贯入;中期受到NEE--SWW向挤压作用,NE向正断层组合和发育于断层之中的含金石英脉受到压扭性变形作用的改造;晚期受到NW--SE向挤压作用,海沟断层表现为右行走滑的特征,NE向断层组合再次受到挤压作用改造,同时形成NWW向和NNW向走滑断层,使早期形成的断层和含金石英脉受到变形改造而发生空间上的错位。3期变形作用很可能是自白垩纪以来发生的,与太平洋板块向欧亚大陆的俯冲作用有关。Based on detailed study of the faults and joints in Haigou gold deposit, the joint occurrences are summarized and analyzed using stereographic projection method. Six preferred occurrences and three joint sets are recognized and their stress field during three stages of deformation is determined. The Haigou gold deposit under- went NW-SE extension at the early stage, which led to the left lateral strike slip of existing EW trending Haigou faults and formed NE trending normal fault at the hanging wall of Haigou fault, associated with the injection of gold- bearing quartz veins. During the middle stage, the deposit underwent NEE-SWW compression, led to the compres- sive reworking of NE trending normal faults and the gold-bearing quartz veins confined in the ore-controlling faults. At the late stage, the compression in NW-SE direction led to the right lateral strike slipping of Haigou fault, the NE trending faults reformed by compression again, and formed NWW and NNW trending strike slipping faults, which led to the deformation and displacement of the earlier faults and gold-bearing quartz veins. The three stages of deformation probably took place during Cretaceous, which related to the subduction process from the Pacific Plate to Eurasian Plate.

关 键 词：构造特征 节理 赤平投影 构造应力场 变形期次 海沟金矿 吉林 

分 类 号：P618.51[天文地球—矿床学] P542[天文地球—地质学]