Heterogeneous conglomerates preserving matrix and clasts caused the complex distribution of pore spaces and can eventually influence fluid flow. To evaluate the influence of complex heterogeneous features in conglomerate rock on both pore distribution and fluid flow, two conglomerate cores were analyzed using X-ray computed tomography (X-ray CT). Conglomerate cores (Core I and Core II) characterized by different distributions of matrix and clasts represented highly heterogeneous features; in Core I (clast-supported conglomerate), clasts were evenly distributed through the entire core, but in Core II (matrix-supported conglomerate), large-sized clasts were dominantly positioned at the bottom of core. Such heterogeneous features caused differences in volume of pores (Core I: 7,409.54 mm3 and Core II: 17,525.83 mm3). Based on X-ray CT image analysis, the numerical model (single-phase fluid simulation) was implemented to evaluate the permeability of conglomerate at different scales. Especially, due to inner heterogeneous features (e.g., matrix, clasts, and cracks) in conglomerate cores, permeabilities were changed significantly dependent on the selected location and size of sub-domains representing a few centimeters (kh and kv: 1.18×10-12 to 1.01×10-10m2). This suggests that the effect of small-scale heterogeneity should be evaluated carefully when heterogeneous conglomerate cores were analyzed. Additionally, the measurement scale for X-ray CT analysis should be large enough to capture such heterogeneous features (e.g., the size of clasts).
|Journal||Journal of Hydrology|
|Publication status||Published - 2021 Nov|
Bibliographical noteFunding Information:
This research was supported by Basic Science Research Program through the National Research Foundation (NRF) of Korea funded by the Ministry of Education [project number: 2016R1D1A1B01008715 and 2021M2E1A1085187]; by the Korea Environmental Industry and Technology Institute (KEITI) [project numbers: 2018002440003]; by the Demonstration-Scale Offshore CO 2 Storage Project in Pohang, Basin, Republic of Korea, funded from Energy Efficiency & Resources of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) which was granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea [project number 20162010201980]. The authors also appreciate financial support by the Basic Research Project of the Korea Institute of Geoscience and Mineral Resources (KIGAM) funded by the Ministry of Science and ICT. This research was partially supported by the Graduate School of YONSEI University Research Scholarship Grants in 2020.
© 2021 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Water Science and Technology