Geological Characterization and Carbon Storage Potential of the Moose Channel Formation in the Mackenzie Delta, Northwest Territories, Canada

The importance of geological carbon storage in reducing anthropogenic CO2 emissions has increased significantly globally and in Canada; however, the storage potential of sedimentary basins in Canada’s Northwest Territories remains unestablished. This first-ever formation-scale assessment of geological carbon storage potential focused on the Basal Sandstone Member of the Moose Channel Formation in the Mackenzie Delta, Canada’s Northwest Territories. We used an integrated approach, combining field observations, laboratory analysis, petrophysical analysis, seismic interpretation, 3D geomodelling, and probabilistic volumetric analysis to establish the reservoir character and long-term storage potential. The investigated reservoir lies in a structurally complex, fault-compartmentalized interval, with an ideal storage zone at 1150 m and 1600 m subsea, deemed adequate for CO2 storage. Petrophysical investigations indicate that the Moose Channel Formation is a heterogeneous reservoir, with porosity ranging from 12.4% to 18.8% and core-based permeability up to 5 mD, whereas the 3D geomodel of permeability shows certain sectors with values up to 35 mD. Moreover, we assessed the caprock’s potential to support long-term CO2 containment based on its low permeability, adequate capillary entry pressures, and regional extent; the caprock succession overlying the Moose Channel Formation was established to support containment and prevent CO2 escape to the atmosphere. 3D geological modeling identified a favorable sub-area within the mapped structural closure where burial depth, porosity, permeability, shale volume, trapping geometry, and reservoir connectivity are most favorable, and which is recommended for further, site-specific characterization. Furthermore, a stochastic Monte Carlo probabilistic volumetric analysis (N = 500,000 realizations, sampling reservoir thickness, porosity, net-to-gross, water saturation, CO2 saturation, and efficiency factor from continuous distributions) was conducted to estimate static CO2 storage capacity, yielding a P90–P50–P10 range of 6.0–12.4–23.3 MtCO2 (mean 13.8 MtCO2; equivalent to an accessible pore volume of 6.9–14.2–26.5 million cubic meters). This study provides a foundation for CO2 evaluation in the Mackenzie Delta and highlights the Moose Channel Formation as a prospective CO2 storage candidate. The present study also requires further analysis, such as geochemical characterization and modeling, fault-seal analysis, and dynamic reservoir simulation, to validate key phases of injectivity and containment performance, leading to the long-term viability of CO2 storage in the Mackenzie Delta.