Abstract:Continental shale oil is a general term for liquid hydrocarbons and many kinds of organic matter in continental organic-rich shale series with vitrinite reflectance of more than 0.5% at buried depth of more than 300 m, and is an important type of source-rock oil and gas. Based on the evolution model of oil generation and expulsion in organic-rich shale series controlled by maturity, continental shale oil is divided into two types: medium-high maturity and medium-low maturity. (1) The continental shale series in China develop high-quality source rocks of freshwater and saltwater lacustrine facies, as well as multiple types of reservoirs, including clastic rocks, carbonate rocks, diamictite, tuff and shale, forming a number of "sweet sections" and "sweet areas" of continuous distribution inside or near source rocks, which have large scale resources. (2) Experimental analysis of organic rich shale samples shows that the shale samples with wavy and horizontal beddings have good storage conditions, and the horizontal permeability of shale is tens to hundreds of times of its vertical permeability, which is conducive to the lateral migration and accumulation of shale oil in the source rocks. (3) After evaluation, the geological resources of medium-high maturity shale oil are about 10 billion tons, which can be effectively developed by horizontal drilling and volumetric fracturing, and will be a practical field of oil exploration in recent years. Shale oil with medium and low maturity has huge resource potential, and technological recoverable resources of (70-90) billion tons, making it a strategic alternative resource of oil industry. However, economic development of this type of shale oil needs in-situ conversion technology breakthroughs. Continental shale oil is an inevitable choice in the process of Chinese continental petroleum exploration from "outside source" to "inside source". Making breakthroughs in the core technologies such as "sweet area" evaluation and optimization, horizontal well volume fracturing and in-situ conversion technology and equipment is the key to realizing scale development of continental shale oil economically.
[1] 赵文智, 胡素云, 侯连华. 页岩油地下原位转化的内涵与战略地位[J]. 石油勘探与开发, 2018, 45(4): 537-545. ZHAO Wenzhi, HU Suyun, HOU Lianhua.Connotation and strategic role of in-situ conversion processing of shale oil underground in the onshore China[J]. Petroleum Exploration and Development, 2018, 45(4): 537-545. [2] 胡素云, 朱如凯, 吴松涛, 等. 中国陆相致密油效益勘探开发[J]. 石油勘探与开发, 2018, 45(4): 737-748. HU Suyun, ZHU Rukai, WU Songtao, et al.Profitable exploration and development of continental tight oil in China[J]. Petroleum Exploration and Development, 2018, 45(4): 737-748. [3] 邹才能, 杨智, 王红岩, 等. “进源找油”: 论四川盆地非常规陆相大型页岩油气田[J]. 地质学报, 2019, 93(7): 1551-1562. ZOU Caineng, YANG Zhi, WANG Hongyan, et al.“Exploring petroleum inside source kitchen”: Jurassic unconventional continental giant shale oil & gas field in Sichuan Basin, China[J]. Acta Geologica Sinica, 2019, 93(7): 1551-1562. [4] 中华人民共和国国家质量监督检验检疫总局, 中国国家标准化管理委员会. 页岩油地质评价方法: GB/T 38718—2020[S]. 北京: 中国标准出版社, 2020. AQSIA, SAC.Geological evaluation methods for shale oil: GB/T 38718—2020[S]. Beijing: Standards Press of China, 2020. [5] 赵文智, 胡素云, 侯连华, 等. 中国陆相页岩油类型、资源潜力及与致密油的边界[J]. 石油勘探与开发, 2020, 47(1): 1-12. ZHAO Wenzhi, HU Suyun, HOU Lianhua, et al.Types and resource potential of continental shale oil in China and its boundary with tight oil[J]. Petroleum Exploration and Development, 2020, 47(1): 1-12. [6] 林森虎, 邹才能, 袁选俊, 等. 美国致密油开发现状及启示[J]. 岩性油气藏, 2011, 23(4): 25-30. LIN Senhu, ZOU Caineng, YUAN Xuanjun, et al.Status quo of tight oil exploitation in the United States and its implication[J]. Lithologic Reservoirs, 2011, 23(4): 25-30. [7] 张新顺, 王红军, 马锋, 等. 致密油资源富集区与“甜点区”分布关系研究: 以美国威利斯顿盆地为例[J]. 石油实验地质, 2015, 37(5): 619-626. ZHANG Xinshun, WANG Hongjun, MA Feng, et al.Relationship between resource-rich regions and sweet spots for tight oils: A case study of the Williston Basin in the USA[J]. Petroleum Geology & Experiment, 2015, 37(5): 619-626. [8] BP. Statistical review of world energy 2019[R]. London, United Kingdom: BP Distribution Services, 2019. [9] U.S.Energy Information Administration. Drilling productivity report: For key tight oil and shale gas regions[R]. Washington, DC, United States: EIA Independent Statistics & Analysis, 2019. [10] 杨智, 邹才能. “进源找油”: 源岩油气内涵与前景[J]. 石油勘探与开发, 2019, 46(1): 173-184. YANG Zhi, ZOU Caineng.“Exploring petroleum inside source kitchen”: Connotation and prospects of source rock oil and gas[J]. Petroleum Exploration and Development, 2019, 46(1): 173-184. [11] 邱中建, 邓松涛. 中国油气勘探的新思维[J]. 石油学报, 2012(S1): 1-5. QIU Zhongjian, DENG Songtao.New thinking of oil-gas exploration in China[J]. Acta Petrolei Sinica, 2012(S1): 1-5. [12] 童晓光, 张光亚, 王兆明, 等. 全球油气资源潜力与分布[J]. 石油勘探与开发, 2018, 45(4): 727-736. TONG Xiaoguang, ZHANG Guangya, WANG Zhaoming, et al.Distribution and potential of global oil and gas resources[J]. Petroleum Exploration and Development, 2018, 45(4): 727-736. [13] 邹才能, 杨智, 崔景伟, 等. 页岩油形成机制、地质特征及发展对策[J]. 石油勘探与开发, 2013, 40(1): 14-26. ZOU Caineng, YANG Zhi, CUI Jingwei, et al.Formation mechanism, geological characteristics, and development strategy of nonmarine shale oil in China[J]. Petroleum Exploration and Development, 2013, 40(1): 14-26. [14] 杨智, 侯连华, 陶士振, 等. 致密油与页岩油形成条件与“甜点区”评价[J]. 石油勘探与开发, 2015, 42(5): 555-565. YANG Zhi, HOU Lianhua, TAO Shizhen, et al.Formation condition and “sweet area” evaluation of tight oil and shale oil[J]. Petroleum Exploration and Development, 2015, 42(5): 555-565. [15] YANG Zhi, ZOU Caineng, WU Songtao, et al.Formation, distribution and resource potential of the “sweet areas (sections)” of continental shale oil in China[J]. Marine and Petroleum Geology, 2019, 102: 48-60. [16] 匡立春, 唐勇, 雷德文, 等. 准噶尔盆地二叠系咸化湖相云质岩致密油形成条件与勘探潜力[J]. 石油勘探与开发, 2012, 39(6): 657-667. KUANG Lichun, TANG Yong, LEI Dewen, et al.Formation conditions and exploration potential of tight oil in the Permian saline lacustrine dolomitic rock, Junggar Basin, NW China[J]. Petroleum Exploration and Development, 2012, 39(6): 657-667. [17] 梁浩, 李新宁, 马强, 等. 三塘湖盆地条湖组致密油地质特征及勘探潜力[J]. 石油勘探与开发, 2014, 41(5): 563-572. LIANG Hao, LI Xinning, MA Qiang, et al.Geological features and exploration potential of Permian Tiaohu Formation tight oil, Santanghu Basin, NW China[J]. Petroleum Exploration and Development, 2014, 41(5): 563-572. [18] 杜金虎, 胡素云, 庞正炼, 等. 中国陆相页岩油类型、潜力及前景[J]. 中国石油勘探, 2019, 24(5): 560-568. DU Jinhu, HU Suyun, PANG Zhenglian, et al.The types, potentials and prospects of continental shale oil in China[J]. China Petroleum Exploration, 2019, 24(5): 560-568. [19] 赵贤正, 周立宏, 蒲秀刚, 等. 断陷湖盆湖相页岩油形成有利条件及富集特征: 以渤海湾盆地沧东凹陷孔店组二段为例[J]. 石油学报, 2019, 40(9): 1013-1029. ZHAO Xianzheng, ZHOU Lihong, PU Xiugang, et al.Favorable formation conditions and enrichment characteristics of lacustrine facies shale oil in faulted lake basin: A case study of Member 2 of Kongdian Formation in Cangdong Sag, Bohai Bay Basin[J]. Acta Petrolei Sinica, 2019, 40(9): 1013-1029. [20] 蒲秀刚, 金凤鸣, 韩文中, 等. 陆相页岩油甜点地质特征与勘探关键技术: 以沧东凹陷孔店组二段为例[J]. 石油学报, 2019, 40(8): 997-1012. PU Xiugang, JIN Fengming, HAN Wenzhong, et al.Sweet spots geological characteristics and key exploration technologies of continental shale oil: A case study of Member 2 of Kongdian Formation in Cangdong Sag[J]. Acta Petrolei Sinica, 2019, 40(8): 997-1012. [21] 杨华, 牛小兵, 徐黎明, 等. 鄂尔多斯盆地三叠系长7段页岩油勘探潜力[J]. 石油勘探与开发, 2016, 43(4): 511-520. YANG Hua, NIU Xiaobing, XU Liming, et al.Exploration potential of shale oil in Chang7 Member, Upper Triassic Yanchang Formation, Ordos Basin, NW China[J]. Petroleum Exploration and Development, 2016, 43(4): 511-520. [22] 付金华, 邓秀芹, 楚美娟, 等. 鄂尔多斯盆地延长组深水岩相发育特征及其石油地质意义[J]. 沉积学报, 2013, 31(5): 928-938. FU Jinhua, DENG Xiuqin, CHU Meijuan, et al.Features of deepwater lithofacies, Yanchang Formation in Ordos Basin and its petroleum significance[J]. Acta Sedimentologica Sinica, 2013, 31(5): 928-938. [23] 杨智, 侯连华, 林森虎, 等. 吉木萨尔凹陷芦草沟组致密油、页岩油地质特征与勘探潜力[J]. 中国石油勘探, 2018, 23(4): 76-85. YANG Zhi, HOU Lianhua, LIN Senhu, et al.Geologic characteristics and exploration potential of tight oil and shale oil in Lucaogou Formation in Jimsar Sag[J]. China Petroleum Exploration, 2018, 23(4): 76-85. [24] 吴松涛, 朱如凯, 崔京钢, 等. 鄂尔多斯盆地长7湖相泥页岩孔隙演化特征[J]. 石油勘探与开发, 2015, 42(2): 167-176. WU Songtao, ZHU Rukai, CUI Jinggang, et al.Characteristics of lacustrine shale porosity evolution, Triassic Chang 7 Member, Ordos Basin[J]. Petroleum Exploration and Development, 2015, 42(2): 167-176. [25] 张欣, 刘吉余, 侯鹏飞. 中国页岩油的形成和分布理论综述[J]. 地质与资源, 2019, 28(2): 165-170. ZHANG Xin, LIU Jiyu, HOU Pengfei.A review on the formation and distribution theories of the shale oil in China[J]. Geology and Resources, 2019, 28(2): 165-170. [26] WU Songtao, ZHAI Xiufen, YANG Zhi, et al.Characterization of fracture formation in organic-rich shales: An experimental and real time study of the Permian Lucaogou Formation, Junggar Basin, northwestern China[J]. Marine and Petroleum Geology, 2019, 107: 397-406. [27] WU Songtao, YANG Zhi, ZHAI Xiufen, et al.An experimental study of organic matter, minerals and porosity evolution in shales within high-temperature and high-pressure constraints[J]. Marine and Petroleum Geology, 2019, 102: 377-390. [28] ZOU C N, YANG Z, TAO S Z, et al.Continuous hydrocarbon accumulation in a large area as a distinguishing characteristic of unconventional petroleum: The Ordos Basin, North-Central China[J]. Earth-Science Reviews, 2013, 126: 358-369. [29] 金之钧, 白振瑞, 高波, 等. 中国迎来页岩油气革命了吗?[J]. 石油与天然气地质, 2019, 40(3): 451-458. JIN Zhijun, BAI Zhenrui, GAO Bo, et al.Has China ushered in the shale oil and gas revolution?[J]. Oil & Gas Geology, 2019, 40(3): 451-458. [30] 邹才能, 潘松圻, 荆振华, 等. 页岩油气革命及影响[J]. 石油学报, 2020, 41(1): 1-12. ZOU Caineng, PAN Songqi, JING Zhenhua, et al.Shale oil and gas revolution and its impact[J]. Acta Petrolei Sinica, 2020, 41(1): 1-12. [31] 杨智, 邹才能, 付金华, 等. 基于原位转化/改质技术的陆相页岩选区评价: 以鄂尔多斯盆地三叠系延长组7段页岩为例[J]. 深圳大学学报(理工版), 2017, 34(3): 221-228. YANG Zhi, ZOU Caineng, FU Jinhua, et al.Selection of pilot areas for testing in-situ conversion/upgrading processing in lacustrine shale: A case study of Yanchang-7 Member in Ordos Basin[J]. Journal of Shenzhen University (Science and Engineering), 2017, 34(3): 221-228. [32] 汪友平, 王益维, 孟祥龙, 等. 美国油页岩原位开采技术与启示[J]. 石油钻采工艺, 2013, 35(6): 55-59. WANG Youping, WANG Yiwei, MENG Xianglong, et al.Enlightenment of American’s oil shale in-situ retorting technology[J]. Oil Drilling & Production Technology, 2013, 35(6): 55-59. [33] 胡素云, 闫伟鹏, 陶士振, 等. 中国陆相致密油富集规律及勘探开发关键技术研究进展[J]. 天然气地球科学, 2019, 30(8): 1083-1094. HU Suyun, YAN Weipeng, TAO Shizhen, et al.Advances on continental tight oil accumulation and key technologies for exploration and development in China[J]. Natural Gas Geoscience, 2019, 30(8): 1083-1094.