基于灰色模糊聚类的压裂水平井见水层段判识方法

Identification Method of Water Breakthrough Interval of Fractured Horizontal Wells based on Grey Fuzzy Clustering Analysis

目前水平井机械找水主要通过井下开关控制逐段生产找水,随着水平井改造段数逐年增加,造成找水测试周期较长,需要将可能见水的射孔段组合进行找水.由于水平井对应注水井多、微裂缝发育造成缝网关系复杂以及超低渗透储层非均质性强,导致来水方向及井筒见水位置判识难度大.以已完成找水措施的水平井各射孔段油藏参数和改造参数为基础,采用灰色关联法对参数优选,并对优选参数进行模糊聚类分析,将聚类结果应用于新见水水平井的出水位置预判,形成一种多段压裂水平井见水层段的辅助判识方法,可将见水层段优化组合,达到缩短水平井找水周期的目的.

Currently the mechanical water detection for horizontal wells mainly controlled by downhole switch when they production, with the number of fracturing segment increased year by year caused a longer period to water detection. So composed possible breakthrough intervals for water detection are necessary. However, due to multi-injection wells correspond- ing horizontal wells, micro-fractures created the fracture network relationship complicatedly and ultra-low permeability reservoir heterogeneity strongly which caused water inflow direc- tion and water breakthrough position in wellbore are identified difficultly. This paper based on reservoir parameters mad fracturing parameters of perforation intervals of horizontal wells those have been completed water detection measures, used grey correlation method to opti- mum parameters, and used fuzzy clustering analysis these parameters. According to clustering results predicted the water breakthrough position of new breakthrough horizontal wells, de- veloped a method which can assist identifying water breakthrough intervals of multi-stage fractured horizontal wells, and these intervals could be optimized, then achieved the purpose of shorten water detection cycle.