页岩气选区评价指标筛选及其权重确定方法——以四川盆地海相页岩为例  

Assessment index selection and weight determination of shale gas plays:A case study of marine shale in the Sichuan Basin

作　　者：郭秀英[1,2] 陈义才[3] 张鉴[4] 满玲[4] 郑海桥 童小俊 任东超 

机构地区：[1]西南石油大学经济管理学院 [2]四川石油天然气发展研究中心 [3]成都理工大学 [4]中国石油西南油气田公司

出　　处：《天然气工业》2015年第10期57-64,共8页Natural Gas Industry

基　　金：国家科技重大专项"页岩气勘探开发关键技术--南方海相页岩气开采试验"(编号:2012ZX05018-006);四川省社会科学重点研究基地四川石油天然气发展研究中心2015年度资助项目"四川盆地及周缘海相页岩气有利目标区优选方法研究"(编号:川油气科SKA15-01)

摘　　要：选择页岩气勘探有利区是一个多指标综合评价的过程,其中,评价指标权重的确定至关重要。针对四川盆地海相页岩具有埋藏生烃史复杂、热演化程度高、经历多期构造运动等特征,筛选出了页岩含气量、页岩有效厚度、有机碳含量等12项海相页岩气选区关键评价指标。鉴于该区海相页岩气选区评价指标多且相互之间关系复杂,不易分组分类,再加上评价指标间两两比较相对重要性的9等级判断矩阵缺乏一致性,导致评价指标权重难以精确确定。为此,根据改进层次分析法原理,在3等级的比较判断调查基础上,构造出评价指标两两比较相对重要性的一致性判断矩阵,同时提出了评价指标主观权重确定改进特征向量法;鉴于主、客观赋权法的不足,进一步提出了综合页岩气选区评价指标主、客观权重的综合权重确定法,并以四川盆地5个海相页岩气区块为例,分析了该方法的可行性与合理性。结论认为:改进的特征向量法克服了层次分析法、特征向量法中判断矩阵的不足,而采用综合权重确定法获得的评价指标权重更能准确体现各评价指标对页岩气选区的重要程度。It is a multi-index comprehensive evaluation process to select favorable shale gas plays,in which the determination of as- sessment index weights is crucial. Marine shale in the Sichuan Basin is characterized by complex burial and hydrocarbon generation histories, high thermal evolution degree, and multiphase tectonic movements. In view of all these characteristics, 12 key assessment indexes for marine shale gas play selection were selected, such as shale gas content, net shale thickness and TOC. Because there are so many assessment indexes that are related in a complicated manner, it is hard to realize index grouping and classifying. Besides, there is no consistency of the 9-grade judgment matrix which is used to evaluate relative importance between the assessment indexes. Therefore, it is difficult to determine the weights of assessment indexes accurately. According to the principle of the improved AHP, the consistency iudgment matrix was constructed to evaluate the relative importance between the assessment indexes on the basis of 3-grade comparative judgment and investigation. Furthermore, an improved eigenvector method was proposed for subjective weights of the assessment indexes. Considering the disadvantages of objective and subjective weight determining methods, an integrated weighting method was put forward with subjective weights and objective weights of the assessment indexes combined. This method was analyzed in terms of its feasibility and rationality with five marine shale gas plays in the Sichuan Basin as examples. It is conclu- ded that the defects of judgment matrix established by AHP and eigenveetor method are eliminated by the improved eigenvector method, and the importance level of each assessment index for shale gas play selection can be accurately presented by the assessment index weights which are computed by the integrated weighting method.

关 键 词：四川盆地 海相页岩 页岩气选区 评价指标 权重 改进特征向量法 综合权重确定法 改进层次分析法 

分 类 号：P618.13[天文地球—矿床学]