低阻致密气藏多学科融合气水解释评价技术

Multidisciplinary integrated gas?鄄water interpretation and evaluation technology for low?鄄resistance tight gas reservoirs

光友会 张子为 彭述兴 郑丽君

中国石油西部钻探地质研究院，新疆 克拉玛依 834000 中国石油长庆油田分公司第一采气厂，陕西 靖边 718500 中国石油长庆油田分公司第四采油厂，陕西 靖边 718500

Research Institute of Geology, Xibu Drilling Engineering Company Ltd., CNPC, Karamay 834000, China No.1 Gas Production Plant, Changqing Oilfield Company, PetroChina, Jingbian 718500, China No.4 Oil Production Plant, Changqing Oilfield Company, PetroChina, Jingbian 718500, China

苏里格西区致密砂岩气藏储层非均质性强，孔隙结构复杂，低阻气层广泛分布，气、水关系复杂，水气比高，无明显分布规律，投产气井产水占比较高，常规气水解释方法符合率低、局限性大。利用地质、试采、测录井等资料综合对研究区储层的含气性进行定性评价，建立了常规解释方法。结果表明：气水分异受储层物性、孔隙结构影响较大，单一参数无明显界限。综合分析储层含气性对测、录井参数的影响，构建多因素参数，创建了“QT-AC交会面”、“挖掘效应”、“气测交会面”、“气测充填系数”4个敏感参数，并进行归一化处理。综合孔隙度、含气饱和度及敏感参数，采用Fisher判别法设立判别函数，建立了气水解释模型，综合解释符合率为84.55%，气层解释符合率为95.08%。经现场应用，与新钻井试气结论吻合较好，该模型满足生产需求。

The tight sandstone gas reservoir in the western Sulige area has strong heterogeneity, complex pore structure, widely distributed low-resistance gas layers, complex gas-water relationship, high water-gas ratio, and no obvious distribution pattern. There were many gas wells of produced water in study area that accounts for a relatively high proportion, and the conventional gas-water interpretation method has a low coincidence rate and large limitations. The gas-bearing properties of the reservoirs in the study area were qualitatively evaluated by using the data of geology, test production and well logging, and a conventional interpretation method was established. The results show that pore structure and reservoir physical property has a great influence on gas-water differentiation, and there was no obvious limit for a single parameter. The influence of reservoir gas-bearing properties on well logging data were comprehensively analyzed, and multi-factor parameters were constructed. 4 sensitive parameters such as "QT-AC envelope surface", "excavation effect", "gas measurement intersection", and "gas measurement filling coefficient" were created and normalized. Conbined porosity, gas saturation and sensitive parameters, Fisher′s discriminant method was used to set up a discriminant function, and a gas-water interpretation model was established. The comprehensive interpretation coincidence rate of model was up to 84.55%, and interpretation coincidence rate for gas layer was up to 95.08%. The interpretation results were in good agreement with gas testing conclusion of newly drilled well in field application test. The model meets the production requirements.

10.6056/dkyqt202204012