Predicting Naturally Fractured Reservoir Location and Characteristics in the Piceance Basin: ABSTRACT

Abstract

Fracture network plays a central role in tight-gas reservoirs such as those in the Piceance basin, Colorado, because it constitutes the major component of the reservoir permeability. The mechanical properties of rocks are complicated functions of mineral composition, texture, temperature, fluid composition, stress and thermal history. A model that accurately predicts the locations of natural fracturing in a basin must account for the interplay of all key processes that affect these characteristics. A fully coupled 3D reaction-transport-mechanical model and simulator has been developed via an interdisciplinary approach. The model is based on the equations of rock fluid interaction, chemical and mechanical compaction, fluid flow, incremental stress rock rheology, and fracture kinetics. The simulator accounts for the major external processes that affect the evolution of the interior of a basin such as tectonic activity, sedimentation, and heat and fluid fluxes at the basin boundary. Detailed well and other geological data for the Piceance basin and rock mechanical property data have been systematically collected and analyzed as the input for model simulations. This unique way of integrating physico-chemical laws and data with geological information gives the model the unique power to reconstruct the fracturing history and to predict the location and characteristicsmore » of naturally fractured reservoirs. Simulation results compared with the observation in the Piceance basin.« less