元坝气田复杂生物礁气藏气水分布精细表征方法

Fine characterization method of gas-water distribution in complex organic reef gas reservoir in Yuanba Gas Field

杨丽娟 王勇飞 张明迪 刘成川 任世林

中国石化西南油气分公司勘探开发研究院，四川 成都 610041

Exploration and Production Research institute, Southwest Oil and Gas Company, SINOPEC, Chengdu 610041, China

生物礁气藏储层非均质性强，气水分布复杂。为了得到与实际气藏更相符的气水分布模型，首先确定储层分类评价指数，如储层质量指数（RQI）、流动单元指数（FZI）和物性综合指数（Zs）等，建立新的储层分类标准；然后据此标准对气藏三维地质模型的储层属性进行分类和分区，并分类赋予归一化后的每类相对渗透率曲线和毛细管压力曲线，达到对流体分布精细刻画的目的。研究表明：综合考虑多个储层物性特征参数和渗流属性参数对岩心实验样品及气藏模型进行分类，更能反映不同类型储层的储渗特征；在基于储渗属性分区的气藏模型中，利用J函数方法重新生成气藏的毛细管压力，并结合各类相对渗透率曲线的端点值，精细描述气藏气水分布特征，能更好地反映气藏流体分布的非均质性。利用该方法建立的数值模拟模型与气藏静动态特征吻合度较高，同时解释了产水井生产动态与前期地质认识不一致的现象。

Organic reef gas reservoir has strong heterogeneity and complex gas-water distribution. In order to obtain a gas-water distribution model that is more consistent with the actual gas reservoir, the reservoir classification evaluation index such as reservoir quality index(RQI), flow zone index(FZI) and aggregative index of physical property(Zs) should be determined to establish the reservoir classification standard. The reservoir property of the gas reservoir 3D geological model is classified and divided based on this standard, and the property is assigned by each normalized relative permeability curve and capillary pressure curve, so as to achieve fine characterization of fluid distribution. The research shows that the classification of core test samples and gas reservoir models by considering multiple reservoir physical property parameters and seepage attribute parameters can better reflect the storage and permeability characteristics of different types of reservoirs. In the gas reservoir model based on storage and permeability property partition, J function method was used to regenerate the capillary pressure of the gas reservoir, and to fine describe the gas?鄄water distribution characteristics of gas reservoirs combining with the endpoint values of various relative permeability curves, which can better reflect the heterogeneity of fluid distribution in gas reservoirs. The established numerical simulation model is in good agreement with the static and dynamic characteristics of gas reservoir. It also explains the inconsistency between production performance of water?鄄producing well and previous geological ideas.

10.6056/dkyqt202203014