Pay Zone Sand Body Formation Causes And Reservoir Physical Property Parameters Study

It is written from reservoir sedimentation mechanism of Gaotai in the light of coring well in the study area. The types of sand body formation causes is judged by investigating pore structure and changes of depositional sequence. Quantitative analysis for the changeable features of sandstone pore structure is done by applying high precise microdigital picture technique. Quantitative analysis for pore texture of reservoir sample from Gaotai is made and explanation technique of the parameters for porosity, permeability and saturation is established. Thus a new way is provided for the study of remaining oil. 　 Reservoirs in South II,III areas, Gaotai are referred to as lacustrine leading edge parfacies. Through core observation, description and analyzing sandstone sedimentary texture, structure, types of sedimentary cycle, variation of sand thickness, sand body geometric form in space, etc. Given the characteristic of logging suites for producing well South II, IV area, 8 parameters are selected including single layer thickness and average thickness, (R0.25/R0.45), trilateral separation of death, sound wave, bore diameter, microelectrode separation and natural potential in single-well logging curves. They are regarded as variables in reservoir physical property parameter predictive experimental formula. By the application of high precise microdigital picture qualitative analysis system, variation pattern between pore structure parameter and observed physical property parameter is found, experimental formula is regressed, variable parameters of every pay zone are determined, finally, projection of sand stone physical property is made by the use of logging curves, through multiple regression analysis, relational expression of reservoir pore structure parameter in Guotai is obtained. By the use of the obtained experimental formula, the parameter calculation is done to pay sets of I-IV high in well of 180-573 high in these areas, relative errors for average permeability, porosity and water saturation are 61%, 8.0% and 13% separately. The experimental formula is quite accurate; projections are done to porosity, permeability, water and oil saturation of the pay sets in Guotai by making use of this formula, and predictive results of every pay zone are obtained. Therefore , it provides foundation for the explanation of reservoir physical property parameter in South II, IV areas, Guotai. Thereby, it fills up the gap in the explanation for the parameters of reservoir porosity, permeability, oil saturation in south II, III areas, Guotai.