Study on identification method of tight sand gas and water in the Su54 Region of Sulige gas field

摘要

The phenomenon of "low-resistivity" gas reservoir and "high-resistivity" water reservoir exist side by side, rapid changes of longitudinal resistivity of the water reservoir and gas and water mixed reservoir in the Su 54 area of Sugeli gas field which caused gas-water identification difficulty. First, the genesis of low-resistivity gas reservoir in tight sand had been analysed. And then, the crossplot acoustic-resistivity method, multiple discriminant analysis method and support vector machine method had been used on gas-water identification method in research. Finally, the gas testing and production dynamic data had been used to verify. The study results show that: the additional conductivity of clay minerals in tight sand reservoir and mud invasion is the main reason for the low-resistivity gas reservoir. And the three gas-water identification methods based on gas testing and production dynamic data made a better recognition effect in practical application; especially the gas-water recognition precision of support vector machine method reaches 93%. This study provides a new thought for the gas-water identification of tight sand gas reservoir.