Abstract:

By using the data of thin section, X-ray diffraction, argon ion polishing scanning electron microscope, mercury injection test, specific surface area measurement, geochemical analysis and oil shale retorting, this paper analyzed the lithology characteristics, mineral components, physical properties and oil potential of the oil shale interval in Damintun Depression, and evaluated the reservoir properties. The results show that the interval of oil shale has the typical “sandwich” structure. The up and low layers are oil shale, with mudstone, sandstone, marlstone and basalt in the middle. The oil shale has pelitic texture, laminar structure and bedding fracture. The content of quartz and carbonate is generally high in oil shale, so it is easy to form oil shale reservoir space, such as structural fractures and dissolved pores. Oil shale and mudstone are relatively homogeneous and they are characterized by small pores and low permeability. The specific surface area, pore diameter and total pore volume of oil shale are all bigger than that of mudstone. The hydrocarbon show of the interval of oil shale is common, especially in sandstone and marlstone, and the gas logging abnormal of oil shale is obvious. Oil content of oil shale is in intermediate level by retorting. The potential hydrocarbon generation amount of oil shale is high, reaching the shale oil enrichment standard by Lu Shuangfang. The formation tests on three old wells are successful and S224 well has mined a lot of shale oil, which proves that the interval of oil shale can meet the shale oil storage requirements in Damintun Depression.

Key words: cross-well seismic, Radon transform, P and Swave, polarization filtering, wave field separation