Analyzing the Well Production Data of Composite Dual Porosity Single Permeability Oil Reservoirs

摘要

Analyzing well production data is one of the important methods for estimating reservoir parameters such as hydrocarbon in place. Recent techniques rely on the use of material balance time to account for variable operating conditions. Many dual porosity reservoirs can be modeled by a composite reservoir. So production data analysis of composite dual porosity single permeability reservoirs is of great interest. Apparently, modern methods have not been applied to complex reservoir models such as composite dual porosity single permeability reservoirs. So the purpose of this article is to analyze production data of such reservoirs with the use of material balance time function. In the first step, a material balance time function is defined in the same way as the single porosity reservoirs and its applicability is confirmed by converting a constant well pressure solution to a constant well rate solution with the use of this time function. It should be noted that the available type curve matching methods cannot be applied to such reservoirs and in this article data analysis is based on the type curveless method. Furthermore, based on the time when each flow regime is observed, a discussion on the analysis of production data with the use of material balance time function for each case is conducted. Finally, applicability and accuracy of the material balance time method for estimation of oil in place of such reservoirs are demonstrated using synthetic reservoir examples.