摘要
以济阳坳陷内典型凹陷陡坡带古近系富有机质页岩为研究对象,在岩心精细观察描述的基础上,通过岩石薄片观察、X射线衍射分析、扫描电镜分析、高压压汞测试以及地化分析等,结合勘探实践,开展陆相断陷盆地陡坡带富有机质页岩基本特征研究,探讨勘探前景,认为陡坡带页岩层系储油和产油条件比盆地中心基质型页岩更为优越;加强陡坡带页岩油认识和勘探力度、刻画砂岩夹层的发育分布将是当今条件下济阳坳陷页岩油获得高产最为现实的途径.研究结果表明:济阳坳陷陡坡带页岩发育厚度2~30 cm的砂岩夹层,(纹)层状灰质泥岩和砂岩夹层是最发育的岩相组合类型;砂岩夹层广泛发育粒间孔和溶蚀孔隙,孔径范围大,宏孔占比高,灰质胶结现象普遍,渗透率远大于页岩基质部分;页岩基质S_(1)为0.5~6.5 mg/g;热演化程度R_(o)适中,多数集中在0.5%~1.0%,整体均处于主生油窗内;相同演化程度下,陡坡页岩油的气油比较高、原油密度较低,可动性强;脆性矿物质量分数平均超过70%,从后期压裂改造角度,陡坡带页岩岩相组合破裂压力低、具有更强的可压性.总体上,与盆地中心基质型页岩相比,陡坡带页岩层系储油和产油条件更为优越.
Paleogene shale in the steep slope zone of typical sag in the Jiyang depression was taken as the research object in this study. Combined with exploration practice, thin section observation, X-ray diffraction analysis, scanning electron microscope analysis, high-pressure mercury injection test, and geochemical analysis, the basic characteristics of shale in steep slope zone of continental fault basin were studied based on the fine observation and description of core. And the exploration prospect was also discussed. Compared with the matrix shale oil in the center of the basin, the shale strata in the steep slope zone have better oil storage and production conditions. Strengthening the understanding and exploration and development of shale oil in steep slope zone and depicting the development and distribution of interlayer will be the most practical way to obtain a high yield of shale oil in the Jiyang depression. The results show that the shale in the steep slope zone of continental faulted basins is mainly composed of laminar calcareous shale and sandstone interlayer with a thickness of approximately 2—30 cm. The porosity and permeability of sandstone intercalation are much larger than that of shale matrix. Intergranular pores and dissolution pores are widely developed in sandstone intercalation. The pore size range of sandstone intercalation is large, the proportion of macropores is high, and the calcareous cementation is widespread. For shale matrix, S_(1) is between 0.5 and 6.5 mg/g, the thermal evolution degree R_(o) is moderate(mostly concentrated in range of 0.5%—1.0%), and all of them are in the oil window. Compared with the matrix shale oil in the center of the basin, the gas/oil ratio of shale oil in steep slope zone is higher, the crude oil density is lower, and the oil mobility is stronger. From the perspective of artificial fracturing, the shale facies combination in steep slope zone has lower fracture pressure and better compressibility with the average content of brittle minerals being above 70%. In general, compared with the matrix shale in the center of the basin, the conditions of oil storage and production of the shale series in the steep slope zone are more favorable.
作者
刘雅利
张顺
刘惠民
王伟庆
包友书
唐东
刘鹏
王勇
李政
王敏
陈涛
LIU Yali;ZHANG Shun;LIU Huimin;WANG Weiqing;BAO Youshu;TANG Dong;LIU Peng;WANG Yong;LI Zheng;WANG Min;CHEN Tao(Exploration and Development Institute of Shengli Oilfield Company,SINOPEC,Dongying,Shandong 257015,China;Shengli Oilfield Company,SINOPEC,Dongying,Shandong 257000,China)
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2021年第6期1108-1118,共11页
Journal of China University of Mining & Technology
基金
中国石化股份公司科技攻关项目(P20049-3,P19017-6)
胜利油田分公司科技攻关项目(YKK1919)。
关键词
陡坡带
页岩油
砂岩夹层
古近系
济阳坳陷
steep slope zone
shale oil
sandstone interlayer
Paleogene
Jiyang depression
