模糊综合评判法在多层气层测试井产能劈分中的应用

评价的定性问题转化为定量问题，层次分析法将不同因素按照相关性大小计算其权值。利用综合评价系数对多层试气中的小层进行综合评判和优选，进而对产能进行合理劈分。给出了评价因素对等级区间隶属度的求取方法以及不同因素之间相对权值的计算方法。通过实例给出了模糊综合评判法进行产能劈分的原理和具体步骤，进一步验证了该方法在鄂尔多斯盆地苏里格气田的应用效果。

关键词：产能劈分；模糊综合评判法；层次分析法；测井学；储层参数；隶属度；苏里格气田

中图分类号：P631文献标志码：A

Application of Fuzzy Comprehensive Evaluation Method in the Production

Dividing of Multilayered Gas Reservoirs of Testing WellsYUE Chongwang1， YANG Xiaoming2， ZHONG Xiaoqin2， PAN Baozhi3， WANG Fei1

（1. School of Geology Engineering and Geomatics， Changan University， Xian 710054， Shaanxi， China；

2. Research Institute of Exploration and Development， Changqing Oilfield Company， PetroChina，

Xian 710018， Shaanxi， China； 3. School of Geoexploration Science and Technology，

Jilin University， Changchun 130026， Jilin， China）Abstract： Production dividing is a key issue in exploration and development of multilayered oil and gas reservoirs of testing wells. There are many factors affecting the productivity of reservoir productivity， and the influences of physical parameters are different. The qualitative problem of comprehensive evaluation was transformed into quantitative problem by fuzzy system theory， and the weights of different factors were calculated by analytic hierarchy process according to different correlations. Small layers in multilayered gas testing well were evaluated comprehensively and selected optimally based on comprehensive evaluation coefficient， and then the productivity of multilayered gas reservoir was reasonably divided. The method of calculating membership of evaluation factors to grade intervals was given， and the calculation method of relative weight between different factors was put forward. Furthermore， principle and concrete steps of fuzzy comprehensive evaluation method for production dividing were proposed with the example. It is verified that the application of the method in Sulige oilfield of Ordos Basin is good.

Key words： production dividing； fuzzy comprehensive evaluation method； analytic hierarchy process； well logging； reservoir parameter； membership； Sulige gasfield

0引言

在油气藏勘探开发过程中，多层测试条件下获取的是多层合采的产能，在实际生产过程中为了合理布置施工，还要了解各小层的产能情况，但由于层与层之间物性参数差异大，非均质性强，影响产能的因素多[18]，所以很难弄清每个小层对产能的贡献，并对后续的增产措施带来了盲目性。因此，如何对多层测试井产能进行合理的劈分对后续施工开发是一个关键性的问题[911]。对于多层测试井的产能劈分，前人常依靠经验来指导现场施工[12]，存在一定的主观盲目性。目前，劈分气井产能常用的方法基于油藏工程原理，但需要大量的测试资料，且气层产能受多种因素影响，因此，其应用效果并不是很理想。对于天然气储层的产能来说，可将每个小层看作一个系统，影响该系统的产能有多种因素，每个因素既相互联系又各自独立，因此，可以将各种因素综合起来，利用测井资料参数对产能进行劈分。本文首先利用模糊系统理论将多因素综合评价的定性问题转化为定量问题[1318]，再利用层次分析法[1924]进一步确定影响小层产能的各因素权重，利用权值对多层试气中的小层进行综合评判和优选，进而对产能进行合理劈分。