Publications

Sisi and Nubi are two gas fields located 25 km offshore the modern Mahakam delta. These fields consist of multiple reservoirs with different geological environments. The main reservoir corresponds to fluvio-deltaic and shallow marine deposits. The fields are divided into more than 300 independent reservoirs defined as GPU (Geological Pressure Units) characterized by their own particular pressure regime, fluids contact and perimeter. Integration of static and dynamic synthesis is obtained by performing a history matching on GPU level with an iterative loop. The aim is to accommodate all available input to achieve a realistic model and ensure the consistency with the data that led to the enhancement in the reservoir behavior understanding. The loop initially started with both static and dynamic initial estimation parameters (fluid contacts, GPU perimeter, bar or channel modeling and connected volume target). Then, this first estimation is confirmed by dynamic simulation whether it satisfied the history (pressure, production, etc). If the result of modeling is incoherent between static and dynamic data, a synthesis revision of input parameters is performed. There are several study cases that will be described in this paper: (1) Extension of a GPU, and (2) Vertical communication between GPU’s. All these cases are presented to emphasize how the iterative loop workflow aids in an improved understanding of reservoir behavior and in the end to better model the reservoir. This integrated and efficient workflow has been used to understand reservoir behavior by focusing on the model regionally. The advantage of this method is to take into account both static and dynamic by not putting more weight on one or the other. These are strong foundations and key points to overcome and to have better understanding of the heterogeneity on Sisi-Nubi Fields which could deliver confident decision in further field developments.