陆东凹陷交力格洼陷九佛堂组页岩油赋存状态及孔径下限表征OA北大核心CSTPCD

Taking Jiufotang Formation in Jiaolige Subsag of Ludong Sag for example,using laser confo-cal microscopy,argon ion polishing and field emission scanning electron microscopy,low-temperature nitrogen adsorption,rock pyrolysis,high-pressure mercury intrusion,and one-dimensional nuclear mag-netic resonance.The microscopic occurrence state of shale oil and the lower limit of occurrence pore size were studied from occurrence state of light and heavy components,pore size change of micropores and full-scale pore size distribution.The results show that both light and heavy shale oil are present in shale pores with various sizes in Jiufotang Formation of Jiaolige Subsag,Ludong Sag.The light oil mainly re-sides in the foliation cracks and macropores,mostly showing honeycomb-,thread-,and lentil-shaped morphologies.The heavy oil resides in foliation cracks,intercrystalline pores,organic pores,micro-dis-solved pores and so on.The lower pore size limit for shale oil occurrence extraction is 3 nm,while the lower pore size limits for free and movable hydrocarbon extraction are 15 and 40 nm respectively.There is a relatively high proportion,with the average of 62.1％,the shale pore size is greater than 15 nm,in-dicating that the oil in the shale has a high mobility potential and thus is feasible to extract.The results provide the basis for future development of shale oil in Jiufotang Formation of Jiaolige Subsag,Ludong Sag.