川西Q地区须家河组储层流体识别方法研究

川西Q地区须家河组储层作为川西坳陷中深层重要气层系之一为典型的致密碎屑岩储层,具有多层系、多类型、多组合的储集体系特点。该区致密碎屑岩钙质含量高,非均质性强,对地层电阻率影响大,储层物性具有低孔低渗高含水饱和度特点,测井解释孔隙度、渗透率参数误差大,气水纵向上间互分布、横向上邻井对比性差导致气水层识别不准确等问题。本文根据不同流体在测井响应上的差别,采用综合指数法（FTI）、电阻率与孔隙度交会图法、正态概率分布法（P1/2）进行流体识别,得到各方法的符合率分别为86.36%、68.19%和90.91%。综合各因素分析,综合指数法（FTI）和正态概率分布法（P1/2）能达到该区准确流体识别的要求,为川西地区须家河组储层的流体识别方法适用性提供了依据。

Study of Fluid Identification for Xujiahe Formations in Q Area of West Sichuan Basin

As one of the most important deep gas sediment groups in West Sichuan depres- sion basin, the reservoir of Xujiahe Formations in Q area is typical of dense detrital reser- voir rocks. The characteristics of reservoir are multi--layer department, multi--type and multi--combination. Due to the much calcium contained in the dense clastic rock, it has strong heterogeneity and great influence on the resistivity of the reservoir. The physical properties of reservoir is low porosity, low permeability and high water saturation. The po- rosity and permeability in logging interpretation have large discrepancy. The gas water forms interstratified layer in vertical direction and has differences between adjacent wells in horizontal direction. All the factors make gas water recognition not accurate. Based on the differences of log response of different fluid categories, this paper has used FTI method, resistivity porosity intersection method, normal frequency distribution method （p1/2） for fluid identification and got the coincidence rate of each method 86.36%, 68.19% and 90. 91%. With the comprehensive analysis of various factors, the FTI method and normal fre-quency distribution method （p1/2） can achieve the requirements of the fluid, which supports the applicability of the method for fluid Formations of West Siehuan Basin. accurate identification of identification in Xujiahe