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

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.