川西ZJ地区须二段致密砂岩储层含气性测井评价

Logging Evaluation of Gas Bearing Properties in the Tight Sandstone Reservoir of the Xu-2 Section in the ZJ Area of Western Sichuan

摘要: 川西坳陷ZJ地区须家河组二段致密砂岩气藏勘探程度低，砂体厚度大，储层非均质性强，储层物性致密，储集条件差，含气性评价困难，气水电性差异微弱。常规的电法测井难以准确反映储层含气性的变化。基于岩心分析、测井、地质、测试等多种资料，对中江地区须二段储层开展了含气性评价方法适应性分析，综合利用常规测井、偶极声波测井以及二维核磁共振测井物理信息，进行了储层流体性质的有效判别。尽管某些测井信息在极为复杂的地层流体识别中存在一定的局限性，但综合多种测井信息及录井全烃显示等资料，基本上达到了有效评价储层含气性的目的。研究成果有效解决了ZJ地区须二段致密砂岩储层含气性评价难题，为后续储量升级，新钻井储层含气性评价，天然气效益开发提供了技术依据。

Abstract: The exploration level of the tight sandstone gas reservoir in the second section of the Xujiahe Formation in the ZJ area of the western Sichuan depression is low, with thick sand bodies, strong reservoir heterogeneity, tight reservoir properties, poor reservoir conditions, difficult gas content evaluation, and weak differences in gas water and electricity properties. Conventional electrical logging methods are difficult to accurately reflect changes in reservoir gas content. Based on various data such as core analysis, logging, geology, and testing, adaptability analysis of gas bearing evaluation methods was carried out for the Xu-2 reservoir in the Zhongjiang area. By comprehensively utilizing physical information from conventional logging, dipole acoustic logging, and two-dimensional nuclear magnetic resonance logging, effective discrimination of reservoir fluid properties was carried out. Although some logging information has certain limitations in the identification of extremely complex formation fluids, by integrating various logging information and logging full hydrocarbon display data, the goal of effectively evaluating reservoir gas content has been basically achieved. The research results have effectively solved the difficult problem of gas content evaluation in the tight sandstone reservoir of the second section in ZJ area, providing technical basis for subsequent reserve upgrading, gas content evaluation of new drilling reservoirs, and natural gas benefit development.