Enrichment mechanism and mode of Jurassic coalbed methane in Ordos Basin

Based on a closed correlativity between the enrichment and formation geological condition of the coalbed methane,from a terrestrial heat flow and geotherm al field,palaeotectonic stress field and groundwater dynamic field, the paper stated the enrichment geologic mechanism of Jurassic coalbed methane in Ordos Basin.The stu dy held that low ground thermal temperature could provide favorable conductions to the methane adsorption of coal reservoirs.An organic configuration between the palaeo tectonic stress field and the seam fractures would favorable to the enrichment of coalbed methane.The Jurassic aquifer system could play a hydrodynamic sealing role to t he enrichment of coalbed methane and some nearly stagnation zone with weak hydrodynamics could be favorable zone of the coalbed methane enrichment.The paper held that the Jurassic coalbed methane formation in Ordos Basin was a typical enrichment mode of the monoclinal structure and the enrichment features of coalbed methane un der the mode were restricted by the mutual coupling relationship of each energy field within the geothermal field,hydrodynamics field and tectonic stress field.