断裂封闭性研究现状及发展趋势

Current research status and development trends of fault sealing

丁文龙 刘天顺 曹自成 李海英 韩俊 黄诚 王生晖

DING Wenlong LIU Tianshun CAO Zicheng LI Haiying HAN Jun HUANG Cheng WANG Shenghui

1. 中国地质大学(北京) 能源学院, 北京 100083; 2. 中国地质大学(北京) 海相储层演化与油气富集机理教育部重点实验室, 北京 100083; 3. 中国地质大学(北京) 非常规天然气地质评价与开发北京市重点实验室, 北京 100083; 4. 中国石化 西北油田分公司, 乌鲁木齐 830011

1. School of Energy Resources, China University of Geosciences (Beijing), Beijing 100083, China; 2. Key Laboratory for Marine Reservoir Evolution and Hydrocarbon Abundance Mechanism of Ministry of Education, China University of Geosciences (Beijing), Beijing 100083, China; 3. Beijing Key Laboratory of Unconventional Natural Gas Geology Evaluation and Development, China University of Geosciences (Beijing), Beijing 100083, China; 4. Northwest Oil Field Company, SINOPEC, Urumqi, Xinjiang 830011, China

断裂控油气作用主要表现在其对油气运移、聚集过程及分布规律的影响,其实质是断裂封闭性问题。断裂封闭性往往是受多种因素控制的，不同地区不同层系在不同地质时期的断裂封闭机制与封闭性主控因素差异较大。目前，断裂封闭性、封闭机理与评价方法还没有形成完整的研究体系，其评价的精度也有待提高。依据全面系统地调研断裂封闭性方面近年来的研究热点，归纳总结了断裂封闭机理，分析了断裂封闭主控因素，梳理了断裂封闭性评价方法，讨论了断裂封闭性研究中面临的实际问题，并提出了未来研究发展趋势。目前，断裂的封闭机理可以分为垂向和侧向封闭机理，前者包括断裂面封闭机理和断裂带排替压力差封闭机理，后者包括砂泥对接封闭机理、泥岩涂抹形成的侧向封闭机理和断裂带高排替压力封闭机理。断裂发育特征、断裂两盘岩性、应力场环境以及压实、胶结、溶蚀等成岩作用是影响断裂封闭性的主要因素，不同因素对断裂封闭性的作用方式不同，断裂在不同位置、不同时期的封闭性有着明显的差别。断裂封闭性评价研究方法可归结为以下4类：(1)传统地质学方法，包括定性分析和半定量分析；(2)数学地质方法，涵盖逻辑信息法、非线性映射分析法、模糊综合评判法、灰色关联分析法等；(3)构造应力场数值模拟及断裂封闭性相关参数计算法；(4)地球化学方法。碳酸盐岩地层断裂启闭机制与封闭性评价、应力和流体及其耦合作用对断裂封闭性的影响机制、多因素的断裂封闭性综合定量评价、断裂封闭性的时空演化及通源能力评估等是未来断裂封闭性研究的发展方向。

The controlling effect of faults on hydrocarbon pool formation is mainly reflected in their impact on the processes of hydrocarbon migration, accumulation and distribution. Its essence is the problem of fault sealing. Fault sealing is typically influenced by a variety of factors, and the mechanism and the main controlling factors of fault sealing differ significantly across different layers, regions and geological periods. At present, there is no complete research system for the evaluation of fault sealing, and the accuracy of its evaluation needs to be improved. By comprehensively and systematically investigating recent research hotspots in the area of fault sealing, we summarize the mechanism of fault sealing, analyze the main controlling factors, systematically categorize the evaluation methods, and discuss the practical issues faced in fault sealing research. We also propose the development trends of future research. Fault sealing mechanisms can be divided into vertical and lateral sealing mechanisms. The former includes fault surface sealing and displacement pressure difference sealing within fault zones, while the latter includes sand and mud juxtaposition sealing, lateral sealing formed by shale smearing, and high displacement pressure sealing within fault zones. The main factors affecting fault sealing include fault development characteristics, lithology of the two fault walls, stress field environment, and diagenetic processes such as compaction, cementation, and dissolution. Different factors influence fault sealing in various ways, and fault sealing varies significantly with location and time. The research methods for fault sealing evaluation can be classified into four categories: (1) traditional geological methods: including qualitative and semi-quantitative analyses; (2) mathematical geological methods: including logistic information method, nonlinear mapping analysis, fuzzy comprehensive evaluation, grey correlation analysis, etc.; (3) numerical simulation of the tectonic stress field and calculation of parameters related to fault sealing; and (4) geochemical methods. Future research directions include fault opening and sealing mechanism and sealing evaluation of carbonate rock strata, the impact mechanism of stress and fluid coupling on fault sealing, comprehensive quantitative evaluations of fault sealing with multiple factors, the temporal and spatial evolution of fault sealing, and the assessment of fault connectivity.

国家自然科学基金面上项目(42072173,42372171)资助。

https://doi.org/10.11781/sysydz202404647