| There are coal-bearing strata and coal-accumulating potential in Houjiaying areas of Fengzhen City in Inner Mongolia Autonomous Region,which is adjacent to the Datong Basin. Based on borehole data in study area, a lot of sino-foreign methods of coal-bearing basin stratigraphy research and investigation of field geology, this paper analyzes the sequence stratigraphic characteristics, the depositional environment and sedimentary facies of Fengzhen basin; according to the analysis of pollen samples, the geological age of pollen samples ,the flora of the ancient climate and palaeoecology and depositional environment of the flora were discussed; using the Seismic Exploration Method, we studied the spatial distribution and range of the bearig-coal formation.1,Based on the paleo-movement surface and regional erosion surface, coal measures in Fengzhen Basin could be divided into 1suppersequence and 2 sequences. Taking the characteristics of the basin structural evolution and lithology into account, the initial lake flooding surface, largest lake-flooding surface and terminal lake-flooding surface are subdivided. Combined with the above-mentioned three boundaries and the lithologic characteristics of coal-bearing strata, the deposit systems of coal-bearing sequence in Fengzhen basin could be divided into lowstand system tract, lacustrine extend system tract, lacustrine wrinkle system tract and non- lacustrine system tract.2,According to the characteristics of sequence stratigraphy and regional geology background, study shows: the favorable environments of forming coal measures are lakeshore swamp, peat swamp and flood plane deposit. The major coal-bearing strata is upper of Datong formation, which belongs to the lacustrine wrinkle system tract and be with commercially valuable. While, Yungang formation only contains thin coal seam, without commercially valuable coal.3,It is found through the analysis of palynomorph that both No.1 and No.2 palynomorph are the products in Early Cretaceous, and No.3 is the product in Jurassic. Therefore, it can be concluded that the weather in Fengzhen region of Early Cretaceous and Jurassic was tropical, subtropical or temperate which was suitable for the propagation of plenty of plants.4,The pattern and range of the coal-bearing strata in Fengzhen Basin is studied by using seismic method. The main coal-bearing strata of the basin are Datong Group, which are distributed throughout the whole basin. The elevation of Datong Group, the coal-bearing strata under the Jurassic, is about 550~1350m. The lowest elevation is located between line D2 and line D3 which is around 550m. The highest elevation is near boundary of the coal-bearing strata is about 1350m. The range of the stratigraphic dip of the study area is about 1°~17°. Moreover the stratigraphic dip near borehole H2-1 is smallest, which in the northwest is largest.5,The research analyzed the structure of the basin using the method of seismic. The faults are more developed in Fengzhen basin, and the essay explained 12 Breakpoint in the pre-inspection districts. According to the law of geological, there are 4 normal faults and 2 isolated breakpoint in this area, Named from south to north and from west to east, They are DF1 ~ DF4 normal faults respectively, and f1, f2 breakpoints.6,Based on drilling data and seismic profiles, it shows that there are no coal seam of industrial value and just coal seam lines and thin coal beds in formation of Yungang Group, thought it is distributed throughout the whole basin; it should not for the future exploration of coal target formation. Tatung Group is widely distributed throughout the basin, which is with the conditions for the formation of industrial value of the coal seam considering the characteristic of sedimentary environment, paleoclimate and structure evolution. Therefore, the coal exploration targets in Fengzhen basin should focus on the future of coal beds of Datong group.
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