Evaluation method for CO2 sealing integrity in shale formations based on combined weighting and 3D modeling
YU Xingchuan1, SHI Xiangchao1, LIU Jianfeng2, GAO Leiyu1, 3, FAN Cunhui1, ZHOU Xiaoli1
(1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, Sichuan 610500, China; 2. College of Water Resources and Hydropower, Sichuan University, Chengdu, Sichuan 610065, China;
3. Production Technology Institute, Daqing Oil Field Company Limited, Daqing, Heilongjiang 163000, China)
Abstract：Existing static sealing evaluation methods exhibit limited applicability to heterogeneous shale formations. To enhance the representativeness and objectivity of evaluation results for the static sealing of CO2 geological storage reservoirs, this study proposes and implements innovative approaches: introducing a three-dimensional heterogeneous model into the traditional evaluation framework; and combining the analytic hierarchy process (AHP) with the entropy weight method (EWM) to establish a comprehensive weighting strategy that minimizes the impact of subjective bias. The research findings indicate that: (1) the evaluation results based on the heterogeneous model (5.84–9.95 points) demonstrate that the sealing performance in most areas of the reservoir meets storage requirements, although there exists a localized leakage risk, effectively addressing the issues of inadequate characterization and overly optimistic outcomes associated with homogeneous models; and (2) the average consistency of the weight coefficients for the primary influencing factors, calculated using AHP and EWM, reaches 83.3%, confirming the effectiveness of the comprehensive weighting strategy in mitigating subjective interference. This method significantly enhances the credibility of static sealing evaluations, providing an efficient and theoretically robust evaluation framework for CO2 geological storage projects.
于兴川1，石祥超1，刘建锋2，高雷雨1，3，范存辉1，周小力1. 基于组合赋权与三维建模的页岩地层CO2封存密封性评价方法[J]. 岩石力学与工程学报, 2025, 44(11): 3011-3023.
YU Xingchuan1, SHI Xiangchao1, LIU Jianfeng2, GAO Leiyu1, 3, FAN Cunhui1, ZHOU Xiaoli1. Evaluation method for CO2 sealing integrity in shale formations based on combined weighting and 3D modeling. , 2025, 44(11): 3011-3023.
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2025, Vol. 44 
