Abstract: Recently, the Ministry of Natural Resources has approved the first-phase proven geological reserves jointly submitted by Sinopec Exploration Company and Jianghan Oilfield for the Middle Jurassic Lianggaoshan Formation in Fuxing area, including 2 010.06×10⁴ tons of crude oil and 123.52×10⁸m³ of natural gas. This marks the emergence of Fuxing oilfield, the first shale oilfield in Sichuan Basin. To further advance the geological theory of terrestrial shale oil and gas accumulation, as well as key exploration technologies, this study systematically analyzes the geological characteristics of terrestrial shale oil and gas in the Jurassic Lianggaoshan Formation based on exploration practices in Fuxing oilfield. The study identifies the main controlling factors for the enrichment and high productivity of shale oil and gas, and proposes key exploration technologies tailored to terrestrial shale oil and gas. Research findings indicate that the upper oil-bearing shale in the lower submember of Member 2 of Lianggaoshan Formation formed in a warm, humid, strongly reducing, and highly productive freshwater environment, characterized by well-developed silt laminae and a high content of feldspar minerals. The combination of Type Ⅱ₁ toⅡ₂ kerogens, medium to high organic carbon content, a high degree of thermal maturity, and high-quality crude oil indicates the development of volatile oil reservoirs in shale. The reservoirs exhibit distinctive geological characteristics, including predominantly inorganic pores and fractures, large pores and throats, integrated pore-fracture networks, and fracture-enhanced drainage. The lacustrine dark shale in the upper oil-bearing layer of lower submember of Member 2 of Lianggaoshan Formation is characterized by excellent material foundation, favorable accumulation configuration, good preservation conditions, and effective fractures, making it a geological-engineering dual sweet spot. This improves reservoir stimulation and enhances hydrocarbons production. To address the challenges associated with terrestrial shale exploration and evaluation, continuous efforts and breakthroughs have been made in well logging, geophysical prospecting, and engineering techniques, thus creating a series of novel, applicable technologies. The discovery of Fuxing oilfield plays a crucial role in advancing the understanding of terrestrial petroleum geology, innovating key exploration technologies, and ensuring national energy security.

Key words: Fuxing oilfield, Lianggaoshan Formation, shale oil and gas, geological characteristics, key technologies

摘要： 近期,自然资源部评审通过了由中国石油化工股份有限公司勘探分公司与江汉油田分公司在复兴地区针对侏罗系凉高山组联合提交的首期探明地质储量,包括原油2 010.06×10⁴t、天然气123.52×10⁸m³,标志着四川盆地首个页岩层系油田——复兴油田诞生。为进一步深化陆相页岩油气成藏地质理论及勘探关键技术,基于复兴油田的勘探实践,系统分析了侏罗系凉高山组陆相页岩油气的地质特征,提出了页岩油气富集高产的主控因素,形成了适用于陆相页岩油气的勘探关键技术。研究结果表明:凉高山组(凉二段)下亚段上油气层页岩形成于温暖湿润、强还原、高生产力的淡水环境,粉砂质纹层发育,长英质矿物含量高;页岩油藏的有机质类型以Ⅱ₁—Ⅱ₂型为主,具中—高有机碳含量和高热演化程度,原油品质优,属挥发性油藏。储层具有"以无机孔缝为主、大孔大喉、孔-缝一体、裂缝输导"的储集特征。凉二段下亚段上油气层湖相暗色页岩具有"物质基础好、成藏配置好、保存条件好、成缝效果好"的特征,是地质-工程双"甜点"层段,有利于储层改造与油气高产。针对陆相页岩勘探评价的难题,持续在测井、物探及工艺方面开展了攻关探索,形成了一系列适宜性的新技术。复兴油田的发现对深化陆相油气地质理论、创新勘探关键技术和保障国家能源安全意义重大。

关键词: 复兴油田, 凉高山组, 页岩油气, 地质特征, 关键技术