Abstract
Most of the Cretaceous fractured reservoirs in Mexico are producing from reservoirs with very poor matrix quality and therefore matrix, for the most part, cannot support the fluid flow into fracture and further on towards the wellbore. Considering other important factors like reservoir rock wettability, which is supposed to be oil wet for this type of rock, small matrix block height, and possible capillary continuity between blocks, the effective production mechanism from these reservoirs (fluid transfer from matrix to fracture) changes from capillary imbibition dominated to gravity drainage and viscos dominated.
Based on the interpretation of field production data as well as discrete fracture network modeling results, most of the movable oil is considered to be stored in the fractured system, and little participation from matrix to the produced fluid is expected. Also considering the very heterogeneous nature of these reservoirs caused by extended systems of faults and fractured, it is very common that this kind of reservoirs can be divided into different compartments with completely different dynamic behavior.
In this work, we try to present a dynamic workflow to compartmentalize the reservoir into isolated or partially isolated blocks, which is the first step in reservoir history-matching process. Later, and through considering the reservoir effective production mechanisms that are discussed in the bulk of the study, a layered history matching process will be presented. In developing this workflow, the raw and interpreted data as well as the final reservoir history-matched models of several fields located in the area have been taken into account to be able to calibrate the workflow and propose a comprehensive procedure that can be of use in similar cases.
