Production indication curve of fracture-cave units in carbonate reservoirs

Abstract

Determining the production performance of fracture-cave carbonate reservoirs is difficult because of the heterogeneous properties of these reservoirs and various production performance levels. Also, data series such as formation pressure and conductivity of fractures are hard to obtain. Thus, common methods, such as the IPR (inflow performance relationship) and water flooding curves, are often ineffective for analyzing of carbonate reservoirs. We propose a new method to analyze the production performance of fracture-cave carbonate reservoirs based on a fracture-cave model delineated by well log and seismic interpretation data, referred to as, the production indication curve. In essence, the production indication curve represents the relationship between flowing bottomhole pressure and accumulated liquid rate, and recoverable reserves can be estimated via the equation of the production indication curve. And it was validated by experiment method which revealed that recoverable reserves calculated by production indication equation was credible. With the production indication curve, recoverable reserve of typical well was estimated, and the results revealed that the proposed production indication curve technique is a dependable method for the characterization of the production performance of fracture-cave carbonate reservoirs.