安徽淮南煤田阜凤推覆体之下的伸展构造及其形成机制

Extensional structure under the Fufeng-nappe in Huainan Coalfield,Anhui Province,and its formative mechanism

报道了淮南煤田阜凤推覆体之下包括犁式断层面、反向正断层、滚动背斜和小型负花状构造在内的伸展构造。这些伸展构造很显然是扬子克拉通和华北克拉通在三叠纪碰撞时 ,大别山造山带前陆位置岩石圈弯曲导致地壳上部产生非弹性变形的结果。根据大别山造山带的形成及相邻地区的构造演化过程判断 ,淮南煤田阜凤推覆体之下的伸展构造是在印支期初露端倪 ,燕山早期 (早侏罗世 )定型 ,燕山中晚期 (中—晚侏罗世 )

The extensional structure under the Fufeng nappe in the Huainan Coalfield,Anhui Province,which consists of shovel like fault,reverse normal faults,small rolling anticline and negative flower shaped structure,is reported in this paper.Such structure in the collision foredeep of the Dabieshan Orogen was resulted in inelastic extensional deformation of the conver side of the flexed plate aroused by lithospheric flexure.Examination of the tectonic evolution of the Dabieshan Orogen and the thrust nappe belt in the south part of the North China Platform from the beginning of the Permian to the end of the Neogene shows that,the extensional structure in the Huainan Coalfield was probably born in the Yindosinian event,finalized in early Yanshanian and fixed position under the Fufeng nappe in middle and late Yanshanian Movememnt respectively.