Quantitative characterization and origin of differences in pore parameter distribution: A case study of the lower cambrian longwangmiao formation in the gaoshiti area of central Sichuan Basin

The research on the developmental characteristics and evolution process of pores in dolomite reservoirs is a hot spot petroleum geology. In this paper, taking Longwangmiao Formation Gaoshiti area as an example, differential distribution pore parameters have been systematically studied combined with downhole cores, logging, cast thin sections, scanning electron microscope data. We used statistical methods image analysis techniques to quantitatively characterize study area. Moreover, factors controlling were identified, namely, lithology, sedimentary facies diagenesis. Finally, mode was constructed. results show that main types developed include intergranular intragranular dissolved pores, intercrystalline mold pores. Among them, are type. surface porosity higher than 0.5% Long 2 Member account for 46% total while those 1 25.5%. Therefore, degree development better Member. addition, granular grain shoal favorable formation large-scale oolitic most reservoir atmospheric freshwater dissolution dolomitization quasi-contemporaneous period; former caused large number dolomitized particles their ring-edge cements latter promoted retention residual dissolution, cementation hydrothermal action burial stage reformation