Majority of the current and predictable naturalgas development within North America is supertight liquid-rich gas reservoirs.Multi-fractured horizontal wells (MFHWs) are commonly used for the developmentof these resources. Rate Transient Analysis (RTA) using single-phase linearflow model is used to characterize the properties of such reservoirs. However,high water production from these reservoirs could misleading the single-phaseRTA analysis and resulted in underestimating the reservoir volumetric. MultiphaseRTA has been used for solving this dilemma by dealing with the production as atotal fluid. The appropriate RTA to be applied to these high waterproducing unconventional plays have long been problematic.
Analyticalmodels or RTA methods are widely used for history matching and productionforecast of unconventional reservoirs. In the current research, a different RTAmethod for analyzing extremely liquid-rich wells is introduced. The method isbased on dealing with the very high water-cut wells as water condensate ones. ThisRTA technique can yield a better estimation of the reservoir properties andsubstantial evaluation of its performance.
By using this methodology, anoptimized development of high water producing unconventional plays can be achievedby effectively designing section spacing and reducing offset fracturecommunication.In this study,RTA method was used to analyze well performancebased on the main flow production, which is water phase. The stimulated surfacearea and estimated ultimate recovery (EUR) have been calculated for the single-phasewater. Whereas, the gas/oil EUR is calculated based on the gas/oil-cutpercentage. The newanalysis methodology can achieve good results comparing to the multiphase RTA,which introduce a simpler and effective methodology to be applied for wellsproducing within high water-cut environments.
The approach of the current study could help petroleum engineers who areforecasting and characterizing very low-permeability liquid-rich shale wellswith high water-cut production. Additionally, this work might introduce adesired method that can be applied to constrain characterization and improve accuracy.