扬子西缘东吴伸展运动  

Extensional Dongwu Movement in Western Margin of Yangtze Region

作　　者：梁定益[1] 聂泽同[1] 宋志敏[1] 

机构地区：[1]中国地质大学地质系,武汉430074

出　　处：《地球科学（中国地质大学学报）》1994年第4期443-453,共11页Earth Science-Journal of China University of Geosciences

基　　金：地矿部行业基金(项目90027)资助

摘　　要：扬子西缘二叠系中震积岩十分发育,笔者根据震积岩、震积—伸展不整合的存在,厘定了它的时代,确认了东吴运动的存在。指出它是该区晚古生代以来最重要的一次伸展构造事件。多旋回震积岩、化石有序混积与水下边界正断层的多次活动有关。在木里地区,从东吴运动开始,地震、伸展—裂陷;火山活动持续到三叠纪,形成裂陷槽（晚二叠世—早三叠世达到高峰）。在这里,东吴运动实际是裂陷造槽运动。Permian seismites are well - developed along the western margin of the Yangtze region. Their presence together with the extensional seismic unconformity have enabled the authors to determine their age and the existence of the Dongwu movement, and to demonstrate also that in the region concerned a significant extensional structural event had taken place by the end of the Palaeozoic. The multicyclothemic seismite, and 'the orderly - disposed fossils within mixed deposits' are related to frequent normal faulting at submarine border. In the Muli area earthquakes, extensional depressions, and volcanism had persisted since the beginning of the Dongwu movement and resulted in ruptured depressions ( reaching its climax by Late Permian - Early Triassic),It is there that the Dongwu movement is practically a depression movement.

关 键 词：伸展不整合 东吴伸展运动 扬子西缘 

分 类 号：P542.2[天文地球—构造地质学]