ABSTRACT: Geologic Models and Flow Simulation Studies of a Shoreface Reservoir: From Stratigraphic Characterization to History Matching
The Meren E-01 Reservoir, Nigeria, a sand-rich wave-dominated deltaic reservoir, was studied from the context of what aspects of stratigraphy affect flow simulation and history matching studies. Work on this project proceeded in three steps. First, the geology of the reservoir was carefully interpreted, and a series of cross-section correlations and maps were defined. In addition, geostatistical characteristics such as variogram type and range were established. Second, a suite of 50 different geologic models were constructed, stressing simple and complex geologic and geostatistical interpretations, and modeling techniques. These 50 models appear visually very different. Third, flow simulations studies were performed. Three stages of flow simulations were performed. First, all models were simulated using unconstrained flow. That is, the producing wells were allowed to drain at unconstrained rates, with the aquifer representing the dominant drive mechanism. Next, all models were simulated, but flow rates at producing wells were fixed to represent the observed rates. Finally, a diverse subset of the 50 models was selected, and rock properties of these models were modified such that flow simulations matched historical data. The conclusions of this study are: 1) simple and complex geologic models of shoreface reservoirs can provide similar predictions of flow performance; 2) unconstrained flow simulations, such as those that may be performed for development studies in which historical data are not available, may be useful predictors of future reservoir behavior.
AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.