Initial Ensemble Design Scheme for Effective Characterization of Three-Dimensional Channel Gas Reservoirs With an Aquifer

• DOI: 10.1115/1.4035515
• Publication Date: 2016-12-20T04:42:52Z
• Authors: Sungil Kim; Hyungsik Jung; Kyungbook Lee; Jonggeun Choe
• Keywords: Characterization; Ensemble forecasting

Reservoir characterization is a process of making models, which reliably predict reservoir behaviors. Ensemble Kalman filter (EnKF) one the fine methods for with many advantages. However, it hard to get trustworthy results in discrete grid system ensuring preservation channel properties. There have been schemes such as cosine transform (DCT) and facies ratio (PFR) improvement reservoirs characterization. These are mostly applied 2D cases, but cannot present satisfactory 3D gas an aquifer because complex production behaviors high uncertainty them. For complicated reservoir, we need reliable initial ensemble members reduce stably characterize models due assumption EnKF, regards mean true. In this study, design scheme suggested EnKF. The reference has 200 × 5 (250 250 100 ft x, y, z, respectively), 15% porosity, two md sand 1 shale. As first step, samples members, show similar water reference. Then, points randomly selected low 5% from sampled members. final remade using data, assumed additional known data. This proposed method characterizes aquifer.