Srms Application to a Regional Open Aquifer: The Basal Aquifer of Western Canada

Abstract

We evaluate the CO 2 Storage resources of the Basal aquifer of Western Canada, where CO 2 is being injected for storage.Storable quantities are classified and categorized using the Society of Petroleum Engineers’ Storage Resource Management System (SRMS) for a notional project. Our notional project consists in injecting CO 2 during 50 years through vertical injectors, no brine producers, and with an aquifer pressurization target of 30% above virgin pressure. The range of resources is derived from petrophysical uncertainties of the aquifers.We evaluate the impact of open boundaries on pressure dissipation and the storable quantities of the formation using the volumetric and simulation methods.We find that the presence of the open boundary increases the storable quantities by approximately 10% only to the resource calculated by compression only.We conclude that, for our notional project, the Prospective Storage Resources or Undiscovered Storage Resources of the Canadian part of the Basal Aquifer range between 19Gt to 32Gt with 25Gt as our base, with a storage efficiency ranging from 0.46% to 0.52%. These storage efficiency estimates are considerably lower than previous dynamic efficiency estimates ranging from 7.4% to 24% (Liu et al., 2014). This illustrates the importance of defining a notional project to estimate its impact on regional pressure, and the significance of the pressure limitation, even for open aquifers.

Keywords: Basal Aquifer of Western Canada, CO2 storage efficiency, Storable quantities, SRMS classification, Notional project, Pressure dissipation