沧东凹陷孔二段低熟页岩纳米孔隙特征及主控因素  

Study on Characteristics and Main Controlling Factors of Nano-pores in Low-maturity Shale Reservoirs in Member 2 of Kongdian Formation in Cangdong Sag

作　　者：张盼盼[1,2,3] 刘小平 关铭[1,2] 孙彪 Zhang Panpan;Liu Xiaoping;Guan Ming;Sun Biao(State Key Laboratory of Petroleum Resources and Prospecting(China University of Petroleum(Beijing)),Beijing 102249,China;China University of Petroleum(Beijing),Beijing 102249,China;China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]油气资源与探测国家重点实验室,北京102249 [2]中国石油大学(北京),北京102249 [3]中国地质大学(北京),北京100083

出　　处：《特种油气藏》2021年第2期20-26,共7页Special Oil & Gas Reservoirs

基　　金：国家自然科学基金面上项目“辉绿岩侵入作用对陆相页岩油源储系统的影响机理研究——以苏北盆地为例”(42072150);“湖相未熟—低熟页岩油形成与聚集机理”(41372144);国家科技重大专项“中国陆相页岩油资源潜力与地质评价研究”(2017ZX05049001-008)。

摘　　要：为深入研究湖相低熟页岩储层纳米孔隙特征和主控因素,选取黄骅坳陷沧东凹陷孔二段12块样品分别进行X衍射、有机地球化学测试、扫描电镜、低温氮气吸附等测试工作,对孔二段页岩储层进行分析。结果表明:沧东凹陷孔二段页岩总有机碳含量为0.48%~7.23%,有机质热演化程度为0.45%~0.84%,整体上处于低熟阶段;页岩纳米孔隙的晶间孔、溶蚀孔隙、有机质收缩缝发育丰度较高,有机质孔次之;纳米孔隙形态整体上呈较开放的状态,孔隙结构以中孔和宏孔为主;页岩孔体积的变化受机械压实、有机质生烃、黏土矿物转化等因素的综合影响,孔体积与黏土矿物含量和总有机碳含量呈一定的正相关性,有机质的赋存形式是页岩有机质孔发育的关键因素。该成果为湖相低熟页岩储层评价提供了理论依据,对湖相低熟页岩资源评价具有一定的参考价值。In order to deeply study the characteristics and main controlling factors of nano-pores in lacustrine low-mature shale reservoirs,12 samples was taken from the Member 2 of Kongdian Formation in Cangdong Sag,Huanghua Depression,and tested for X-ray diffraction,organic geochemical testing,electron microscopy scanning,and low-temperature nitrogen adsorption to analyze the shale reservoirs in Member 2 of Kongdian Formation.The results indicated that the total content of organic carbon of the shale in the Member 2 of Kongdian Formation in Cangdong Sag was 0.48%to 7.23%,and the thermal evolution of organic substances was 0.45%to 0.84%,indicating that the shale was in the low-mature stage as a whole;the nano-pores in the shale were developed with an abundance of intercrystal pores,dissolved pores and shrinkage joints of organic substances,followed by organic substance pores;the nano-pores were relatively open as a whole,and mainly composed of mesopores and macropores in structure;the shale pore volume was changed mainly by the comprehensive effects of mechanical compaction,hydrocarbon generation of organic substances,transformation of clay minerals,and other factors;there was a positive correlation between pore volume and mineral content in clay and total content of organic carbon;the occurrence form of organic substances was the key factor for pore development of organic substances in shale.The results provide a theoretical basis for the evaluation of lacustrine low-maturity shale reservoirs,and serve as references for the evaluation of lacustrine low-maturity shale resources.

关 键 词：页岩储层 影响因素 孔隙特征 低成熟 孔二段 沧东凹陷 

分 类 号：TE122[石油与天然气工程—油气勘探]