摘要
通过对江西南城地区侏罗系林山群与下伏前泥盆纪变质地层、白垩纪地层与前白垩纪地层接触关系调查和谢家构造窗、竺由新村构造窗、上乌石构造窗、望天石飞来峰的发现及钻孔验证,初步厘定了区内燕山期滑覆构造和喜马拉雅期推覆构造。燕山期滑覆构造发生在中侏罗世末,主滑面沿华力西—印支构造层(D—T2)、燕山构造层(T3—K1)与下伏地层间角度不整合面扩展而成,泥盆纪—早白垩世地层为滑覆体,滑覆在前泥盆纪变质地层之上,动力学来源为太平洋板块由南东向北西对欧亚板块俯冲。喜马拉雅期推覆构造规模大、动力学机制复杂(顺层和切层推覆),彻底打破了华南地区原有的地层沉积层序,形成了现存的横向分带、纵向分层的多层叠瓦、堆垛推覆构造格局。前白垩纪地质体为外来推覆体,由南东向北西推覆堆垛在白垩纪地层之上,白垩纪地层呈"构造窗"分布于前白垩纪地质体之下,动力学来源可能为印度板块与欧亚板块碰撞形成。
Based on geological surveying and drilling verification of stratum contact relations both between Jurassic Linshan Group and underlying Pre-Jurassic metamorphic strata and between Cretaceous and Pre-Cretaceous strata,this study has newly found the Xiejia structural window,Zhuyouxincun structural window,Shangwushi structural window and Wangtianshi klippe,and moreover,has determined the Yanshanian glide and Himalayan thrust nappe structures in Nancheng area,Jiangxi. The Yanshanian glide structure occurred in the end of Middle Jurassic along the expanding surface from unconformity surfaces between D-T2/ T3-K1（ gliding nappe） and lower strata（ underlying strata）. The dynamics of glide structures maybe relate to the subduction of Pacific plate from southeast toward northwest. The large-scale Himalayan thrust nappe structure had thoroughly altered the former strata sequence and formed present tectonic framework. This framework is composed of multiple imbricated thrust and stacking faults（ bedding and cross-bedding） and behaves a feature of lateral zonation and vertical stratification. The allochthon Pre-Cretaceous mass thrusts from southeast toward northwest and stacks on the autochthon Cretaceous strata. The autochthon Cretaceous strata exhibit some windows around by Pre-Cretaceous.The dynamics of Himalayan thrust nappe structure is complicated and maybe relate to the distant effect of the collision between the Eurasian plate and the Indian plate.
出处
《现代地质》
CAS
CSCD
北大核心
2016年第1期97-109,共13页
Geoscience
基金
中国地质调查局项目"江西1:5万南城县
龙湖
株良
资福幅区域地质调查"(1212011120873)
关键词
推覆构造
滑覆构造
中—新生代
江西南城
thrust nappe structure
sliding nappe structure
Mesozoic-Cenozoic
Nancheng,Jiangxi
