摘要
利用多重反演方法(Multiple Inverse Method,MIM)恢复永平铜矿多期古构造应力场,该方法可以划分形成断层擦痕的多个古构造应力期次。研究表明,永平矿区印支期以来至少受到3期古构造应力场作用,进而探讨了永平铜矿构造演化历史。第一期构造应力场为EW方向的近水平挤压,形成轴向近SN的褶皱,以及走向近南北的逆断层;第二期构造应力场为NW-SE方向近水平挤压,伴随着岩体的侵入,导致层间破碎带的矽卡岩化和矿体形成;第三期构造应力场为EW方向的再次挤压作用,造成控矿断层推覆距离加大,混合岩和矽卡岩破碎带向西逆冲推覆到晚古生代地层之上。
Multiple Inverse Method is useful for separating stresses from heterogeneous fault-slip data. By using the method applied to fault slip data in the Yongping Copper Deposit, three phases of palaeotectonic stress were found since the Indosinian. At first, E-W direction of compressive stress field formed S-N direction of folds, faults and interlayer fracture zone. Then the tectonic stress field transformed as NW-SE direction. Accompanied by the intrusion of pluton, thermal metamorphism occurred on interlayer fracture zone. Hydrochloride rock changed into skarn and mineralization. At last, E-W direction of compressive stress leads to increasing nappe distance. As a result, migrnatite and skarn thrust over Paleozoic strata from east to west.
出处
《地球科学进展》
CAS
CSCD
北大核心
2013年第5期608-617,共10页
Advances in Earth Science
基金
中国地质调查局项目"中国显生宙重要地区陆壳聚散的基本框架与成矿制约"(编号:1212011120160)资助
关键词
古构造应力场
永平铜矿
断层擦痕
多重反演方法
Palaeotectonie stress fields
Yongping Copper Deposit
Fault-slip data
Multiple Inverse Method.
