Reservoir Quality Prediction in Frontier Basins

Abstract

Reservoir quality prediction is a critical element in exploration projects worldwide. Porosity and permeability of reservoir sandstone are determined by the texture and mineralogical composition of the grains, and diagenetic modifications (compaction and cementation) in response to burial. Therefore, reservoir quality predictive models benefit greatly from petrographic description and measured core analysis of reservoir sandstones in the area of interest, and a petroleum system model that captures changes in temperature, effective stress, and overpressure from time of deposition to the present day. A challenge for reservoir quality prediction in frontier basins is the lack of sandstone petrographical information and measured porosity and permeability data. In order to address this problem, we developed a method and workflow for reservoir quality prediction in areas with limited or no reservoir data which combines hinterland sediment compositional studies with Touchstone modelling of appropriate sandstone analogue data sets. The goal of the hinterland workflow is to develop an understanding of paleo-drainage patterns and predict sediment composition entering the basin. Existing Touchstone models of sandstones that reflect compositions in accordance with the hinterland study results are then used to forward model likely porosity and permeability outcomes for frontier basin locations. We tested our workflow on several mature exploration basins in order to prove concept, before applying this method in frontier regions. We learned that the best results are achieved when the selected analogue sandstones are age-equivalent to the target reservoir, and that utilizing six or more different analogue data sets yield statistically consistent results. The output of our reservoir quality prediction workflow provides valuable insight into a frontier basin's economic basement. This method can be utilized when a company has a large number of petrographic data sets from various basins worldwide, and has access to Touchstone reservoir quality prediction software.

AAPG Datapages/Search and Discovery Article #90291 ©2017 AAPG Annual Convention and Exhibition, Houston, Texas, April 2-5, 2017