Sequence stratigraphy and coal accumulation pattern of the Early Cretaceous coal measures in Hailar Basin, Inner Mongolia
Guo Biao1, Shao Longyi1, Zhang Qiang2, Ma Shimin1, Wang Dongdong3, Zhou Qianyu1
1.College of Geoscience and Surveying Engineering,China University of Mining and Technology(Beijing),Beijing.100083 2 Coal Geology Survey Institute of Inner Mongolia Autonomous Region Coalfield Geological Survey,Hohhot.010010,Inner Mongolia 3.College of Geological Science and Engineering,Shandong University of Science and Technology,Qingdao.266590,Shandong
Abstract：Sequence stratigraphy and coal accumulation pattern of the Early Cretaceous coal measures in Hailar Basin have been studied using outcrop and borehole data in this paper. Based on the regional unconformity surface,the erosional base of incise valley filled by sandstone and conglomerates, the vertical facies reversal surface and paleontological discontinuous surface,6 third-order sequences were divided in Hailar Basin. Tongbomiao Formation was developed at the initial subsiding stage. Nantun Formation was developed during the rapid subsiding stage. Damoguaihe Formation was formed in the strong extension stage and Yimin Formation was developed during the basin shrinkage stage. The distribution of the Early Cretaceous coal measures showed best in the eastern and northern, middle part come secondly, and southwest worst. Coal accumulated in the Yimin Formation and the second member of Nantun Formation,where the tectonic subsidence was showing the characters of intermittence,concussion and multi-cyclicity,providing the balance between the increasing rate of accommodation space and the peat accumulating rate favored the accumulation of the regional thick coal seams.
Guo Biao,Shao Longyi,Zhang Qiang et al. Sequence stratigraphy and coal accumulation pattern of the Early Cretaceous coal measures in Hailar Basin, Inner Mongolia[J]. JOPC, 2014, 16(5): 631-640.
