Triassic The Xiangxi Groups In Hong Sec Gas And Water Distribution Characteristics And Genetic Mechanism Of Sichuan

As the displacing force and carrier,the groundwater play an important role all the way for producing, migration, accumulation and dissipation of petroleum in the pool-forming.The hydrochemistry and hydrodynamics is one of the factors for the chemical and physical change of petroleum.Through the analysis on geochemistry of palaeohydrology,we can know the origin of the oilfield water and then conclude the geofactor and the geochemical factor of the formation water.Through the study and the comeback of the palaeohydrodynamic field, we can judge the migration direction of the petroleum,the separate between gas and water,and the relation between the petroleum and the pool.The study of the reservoirs' geohydrochemistry is the process to investigate the characterstics of reservoirs' geohydrochemistry in the oil- and gas-bearing basin.It is one of the contents for the study of the oilfield's geohydrochemistry to search the petroleum field by hydrochemical ingredients and forecast the latent buried pool.In basin,there is an active element change between the groundwater and the petroleum.Because of the geohydrochemistry factor for the transfer of elements,the chemical ingredients of water change.Simultaneusly,the pool arose the transfer of the elements and the chemical ingredients of water tend to or achieve homeostasis(Chroma and so on).So through the study of chemical ingredients of groundwater,the distribution of petroleum and water is forecasted,and also do the favourate area and structure for petroleum accumulation.Layer 4 in Upper Triassic Xiangxi Group(T₃x₄) of the central area in Sichuan has loe porosity and permeability,The physical character of the reservoir is bad.The gas and water layers develop in the middle and lower parts of T₃x₄ ,The gas and water distribution is controlled by lithology,and the structural change only has the assistant function,The unconventional lithology-structural gas reservoir and lithology gas reservoir are coexistent.The gas-water distribution relation has differences in different regions or different structural belts,The relative steady siope regions are favorable for oil and gas accumulation by the lithology trapkand the high-steep structural parts of the central area in Sichuan are faborable for the oil and gas accumulation by lithology-stuctural trao,So,the distribution rule...