Analysis and Application of Production Logging Data in Shale Gas Well

Abstract

Abstract Production profile logging is an efficient method for production dynamic monitoring and post-fracture effect evaluation in shale gas plays, the method can realize the rule of gas production and water flowback and understand the downhole production situation, it is important to optimize well trajectory, well completion and gas production system. However, the fluids in downhole are mix phases usually, they are composed by gas and hydraulic fraturing fluids in the process of gas production, the flow regimes and status are complicated in horizontal well, in addition, the flow regimes are affected by well diameter and well inclination, thereby, the method of logging data interpretation becomes far more difficult. This paper researched the interpretation method of production logging data firstly in horizontal well, analyzed the production rate distribution in each fracture in a shale gas well. Subsequently, the paper investigated the fluid phase and flow regimes with the image function of array holdup tools, the water recirculation happened in the stage of dogleg postion. In addition, the paper built the sensivity analysis of openhole logging data and hydraulic fracturing parameters with production logging results, analyzed the main impact fators of gas production contribution in the well. At last, Models with non-uniform fracture properties are built to take into the consideration of production logging results, production rate and estimated ultimate recovery (EUR) are predicted by the models with uniform fractures and non-uniform fractures for the case well. From the analysis results of production logging data, it illustrated that only about one third to one half of hydraulic fractures had produced gas. Meanwhile, the productive fractures contribute differently to the gas production rate. There was a lot of water in the wellbore acoording to the dynamic leve of the water. The sensitivity analysis indicated the geology properties and hydraulic fracturing parameters are not main impact factors of gas production distribution unevenly in the well. In addition, models with non-uniform fractures and with uniform fracture are built for this case well. Both models can get satisfying log-log plot and history match. Gas rate and pressure transient analysis with non-uniform fractures model gets higher estimated ultimate recovery (EUR) than the one with uniform fractures model. Through the analysis and application of production profile logging data, understanding the gas flow state in shale gas well, improving the application level of logging data, and the researched results can provide the reasonable suggestions for afterward well trajectory, well completion and produciton optimazition.