Reservoir heterogeneity is the key factor which impact production, the water flooding efficiency and ultimate hydrocarbon recovery during the reservoir development. Reliable productivity evaluation from early stage is needed to understand reservoir characteristics and minimize the uncertainty of production potential, so that the solution could be prepared for the technical challenges in the development phase. Evolution of wells drilled at high overbalance with water-based mud typically shows the following challenges: severe near-wellbore formation damage, complex pore structures due to complex the lithology system and big discrepancy among permeability from different measurement source. The productivity analysis becomes complicated and affected by the interpretation methods under different measurement environment.
A comprehensive case study is presented in this paper for the productivity evaluation in high heterogeneous reservoir at high overbalance drilling. An integrated approach is elaborated to overcome the challenges by integrating all available data from data acquisition. Different scaled permeability from open-hole logs, MDT pretests, mini-DST and DST is integrated systematically to understand the vertical and horizontal direction of reservoir heterogeneity. From the integrated data analysis, the interpreted reservoir properties are upscale and populated into numerical model and validated through history matching by dynamic tests. This integrated methodology or study provides the attractive and efficient way to evaluate the productivity in the early stage of reservoir lifecycle, and it minimizes the uncertainty of production potential by understanding the reservoir characteristics. At the end, the suggestions are concluded according to this comprehensive study.