Study on pore morphology of Shale oil reservoir in Da'anzhai Member in central Sichuan Basin
The Da'anzhai Formation lacustrine shale is a key target for shale oil exploration in the Sichuan Basin.To understand its microscopic pore characteristics,this study used argon ion polishing,scanning electron microscopy,and image processing software to extract pores from high-resolution electron microscope images and obtain parameters such as pore diameter,roundness,and elongation ratio for different pores.The results indicate that the black shale of the Da'anzhai Formation contains two classes and seven common pore types,primarily clay pores,quartz/calcite crystal pores,grain-edge pores,and organic pores.Different pore types exhibit significant morphological differences,with organic pores being small with a roundness approaching 1,clay intercrystalline pores and grain-edge pores having small roundness convexity values and large elongation ratios,and calcite crystal pores being large with relatively large roundness convexity.Pore size and shape are controlled by composition and compaction:inorganic pores generally have larger diameters than organic pores,with inorganic pores in brittle minerals having the largest diameters,often polygonal,while inorganic pores in plastic minerals have smaller diameters and are often elongated.
NETL
NSTL
万方数据
