松辽盆地中央坳陷区三肇凹陷上白垩统青山口组一段页岩含油性特征

Oil-bearing capacity of shale in the first member of Upper Cretaceous Qingshankou Formation, Sanzhao Sag, Central Depression, Songliao Basin

康淑娟 仰云峰 王华建 江文滨 何坤 刘冉冉

KANG Shujuan YANG Yunfeng WANG Huajian JIANG Wenbin HE Kun LIU Ranran

中国科学院深地资源装备技术工程实验室(中国科学院 地质与地球物理研究所), 北京 100029 中国科学院页岩气与地质工程重点实验室(中国科学院 地质与地球物理研究所), 北京 100029 中国科学院 地球科学研究院, 北京 100029 中国科学院大学, 北京 100049 苏州中科地星创新技术研究所, 江苏 苏州 215163 中国石油勘探开发研究院, 北京 100083 中国科学院 力学研究所, 北京 100190 大气边界层物理和大气化学国家重点实验室(中国科学院 大气物理研究所), 北京 100029

CAS Engineering Laboratory for Deep Resources Equipment and Technology (Institute of Geology and Geophysics, CAS), Beijing 100029, China CAS Key Laboratory of Shale Gas and Geoengineering (Institute of Geology and Geophysics, CAS), Beijing 100029, China Innovation Academy for Earth Sciences, CAS, Beijing 100029, China University of Chinese Academy of Sciences, Beijing 100049, China Suzhou Innovation Research Institute of Earth and Planetary Sciences, Suzhou, Jiangsu 215163, China PetroChina Research Institute of Petroleum Exploration & Development, Beijing 100083, China Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (Institute of Atmospheric Physics, CAS), Beijing 100029, China

松辽盆地中央坳陷区上白垩统青山口组湖相暗色页岩沉积蕴含了数量可观的页岩油资源，其中齐家—古龙凹陷青山口组页岩油勘探已取得重大突破。采用井场密闭热释方法，结合室内溶剂抽提和比较热解方法，综合评价松辽盆地中央坳陷区三肇凹陷青山口组一段页岩含油性特征。结果表明，研究层段青山口组页岩总有机碳含量介于1.48%~6.97%，平均3.40%，Tmax值(抽提后)介于440~453 ℃，平均448 ℃，产率指数(PI)介于0.28~0.67，表明青山口组一段页岩处于大量生油阶段。井场和室内相结合的评价方法获得的页岩油含量介于4.00~19.49 mg/g，平均13.74 mg/g；其中游离油含量介于3.41~13.63 mg/g，平均8.70 mg/g；束缚油含量介于0.60~9.43 mg/g，平均5.04 mg/g。游离油由受限油和可动油组成，受限油含量介于1.81~8.49 mg/g，平均4.15 mg/g；可动油含量介于1.36~11.05 mg/g，平均4.55 mg/g，两者比例约为1∶1。以可动油含量平均值推算，可动油资源量为12 kg/m3，揭示三肇凹陷青山口组一段具有良好的可动页岩油资源潜力。

The lacustrine dark shale deposits of the Upper Cretaceous Qingshankou Formation in the Central Depression of Songliao Basin contain a considerable amount of shale oil resources, among which the shale oil exploration of the Qingshankou Formation in the Qijia-Gulong Sag has made a major breakthrough. In this paper, methods of sealed thermal release, combined with organic solvent extract and Rock-Eval, has been used for the comprehensive evaluation of shale oil-bearing capacity of the Qingshankou Formation. The TOC of shales from the Qingshankou Formation in the study area range from 1.48% to 6.97% with an average value of 3.40%. The values of Tmax range from 440 ℃ to 453 ℃ with an average of 448 ℃ for the samples after extraction, and the production index ranges from 0.28 to 0.67, indicating a middle stage of oil generation window. The shale oil contents of the studied samples range from 4.00 mg/g to 19.49 mg/g with an average value of 13.74 mg/g. The contents of free oil range from 3.41 mg/g to 13.63 mg/g with an average value of 8.70 mg/g; while the content of adsorbed oil ranges from 0.60 mg/g to 9.43 mg/g with an average value of 5.04 mg/g. Free oil is made up of restricted oil and movable oil in the proportion of 1∶1. The content of restricted oil of the studied samples ranges from 1.81 mg/g to 8.49 mg/g with an average of 4.15 mg/g; while the content of movable oil ranges from 1.36 mg/g to 11.05 mg/g with an average of 4.55 mg/g. The movable oil resource is 12 kg/m3 based on the average content of mobile oil, which reveals good resource potential of movable shale oil in the first member of Qing-shankou Formation of the Sanzhao Sag.

中国科学院战略性先导科技专项 XDA14050204

https://doi.org/10.11781/sysydz202301089