基于主客观赋权与功效系数法的储气库断层密封性评价方法OA

Faults are weak links in depleted oil-and-gas-reservoir underground gas storage facilities.The numerous factors affecting fault sealing,their complex in-teractions,and the ambiguity of indicator weights pose challenges to comprehensive evaluation of fault sealing in gas storage facilities.In view of this,a comprehen-sive evaluation method for fault sealing based on"combined subjective-objective weighting-the efficacy coefficient method"was proposed.A fault sealing evalua-tion index system was established from four aspects,namely fault lithologic characteristics,environmental conditions,mechanical characteristics,and injection-pro-duction system.The DEMATEL method and the anti-entropy weighting method were jointly used to determine indicator weights,thereby reducing the bias caused by weighting with a single method.By calculating the total efficacy coefficient of gas storage faults,the sealing performance grade of faults in gas storage facilities was quantitatively determined.This evaluation method was applied to a gas storage facility in the Bohai Bay Basin.The results show that the sealing grade of the gas stor-age facility is Grade Ⅲ(relatively good),and the calculated results are consistent with actual field conditions.This evaluation model is feasible and can provide a comprehensive assessment of the sealing performance of faults in underground gas storage facilities.These results can provide a theoretical reference for site selection and fault sealing evaluation of underground gas storage facilities.