江西萍乡——乐平地区推覆构造

NAPPE STRUCTURE IN THE PINGXIANG-LEPING AREA JIANGXI

摘要: 萍—乐坳陷及其基底存在不同层次的滑脱,并由宜春盆地滑覆系、九岭南缘逆冲推覆系和乐平逆冲推覆系组成一个规模宏大的复杂推覆系。推覆系内部存在三种不同的结构类型:基底逆冲叠瓦式、盆地盖层对滑式和盆岭对冲式。盖层区逆冲断层扩展的主导因素是盖层底部不整合面的拆离,后继作用是多层次滑脱和随后的切层逆冲,扩展顺序由盆内指向盆缘,即内序列。推覆作用主要导源于东秦岭中生代的陆内俯冲,分三个推覆期:印支期、燕山早期和喜马拉雅期。

Abstract: There exist detachment structures at different levels in the Pingxiang- Leping depression and basement,forming a large-scale nappe structure—— the Pingxiang-Leping complex nappe system.The structural types within the system include the basement thrust imbricate type and basin-range ramp type.Overthrusting was mainly derived by Mesozoic intracontinental subduction in the East Qinling Mountains.There were three overthrusting stages:the Indosinian,early Yanshanian and Himalayan stages.