Abstract:Enhancing porous evolution of shale, especially assessing the relationship of porous evolution and residual hydrocarbon quantitatively, is of great significance for petroleum exploration in shale. Preventive lacustrine source rocks of type I with low maturity in Ordos Basin are collected and selected for modeling experiment of physical diagenesis in shale, combing with geological constrains of burial history, formation pressure and formation water salinity. Utilizing methods of mercury intrusion, nitrogen adsorption,CO2 adsorption we acquire specific pore volume, specific surface area and pore size distribution of shale in different temperature and pressure. In combination of ultrasonic extraction of bitumen “A” in trichloromethane, we try to figure out the relationship of porous evolution and residual hydrocarbon. Ultimately, we seek to interpret porous alteration by integrating analysis of TOC, XRD in whole rock and XRD in clay minerals Results show that specific pore volume of macropores increase and then decrease with residual hydrocarbon, while in micropores and mesopores, specific pore volume decrease first and then increase with the rises of modeling temperature. XRD analysis presents that mineral contents are the controlling factor of macropores, and TOC and contents of clay minerals control micropores and mesopores. Enlargement of specific pore volume in micropores and mesopores implies remarkable reservoir space for shale gas generated in high-over maturity stage of kerogen pyrolysis and oil cracking. Specific pore volume of macropores varies consistently with residual hydrocarbon. Increase of macropores in oil window response to the favorable entrapment zones of shale oil.