Capacity assessment of CO2 sequestration in deep saline aquifers: insights from mindong no. 1 mine

This study aims to assess the CO 2 storage capacity of the second member of the Damoguaihe Formation beneath the Mindong No.1 Mine area in the Hailar Basin, China, by constructing a three-dimensional geological model that accounts for geological uncertainties. Well logging and geological data were used to develop a 3D rock physics model focusing on two units (K 1d-2 and K 1d-4 ) of the Damoguaihe Formation sandstone section, with reservoir depths ranging from 730 m to 820 m. The rock physical properties were predicted using well logging curves and borehole column diagrams. To evaluate uncertainty in reservoir pore volume, between 100 and 900 simulation cases were generated, with 300 cases selected as the optimal approach for addressing geological variability. Rock physics interpretation revealed that the sandstone reservoir exhibits high porosity, medium permeability, and a high net-to-gross ratio. The static model indicated lateral heterogeneity in reservoir properties and lithofacies, identifying K 1d-2 and K 1d-4 as the most favorable reservoir units. Based on the rock physics model, the rock volumes for these two units within the K 1d block were calculated as 596 × 10 6 m 3 and 981 × 10 6 m 3 , respectively, yielding a total volume of 1,577 × 10 6 m 3 . The estimated geological CO 2 storage capacities for the K 1d-2 and K 1d-4 formations ranged from 0.528 × 10 6 t to 2.15 × 10 6 t. The results demonstrate a practical CO 2 storage potential of 0.52–2.1 million tonnes within the study area, confirming that the Damoguaihe Formation represents a viable candidate for future carbon capture and storage (CCS) projects in the Hailar Basin.