Pore space characterization of carbonate materials is of fundamental importance to a wide range of earth science and engineering applications. In this study, we show how confocal microscopy can be used as a reliable tool to visualize and quantify the heterogeneous pore space in carbonate materials. In confocal imagery, the quality of pore space images is controlled by various factors including the choice of fluorophore, objective lens, and medium of imaging. Our experiments demonstrated that there is no “fit-for-all” dye. The red dye provides more depth of investigation, while the blue dye can capture large pores more efficiently. Our investigation indicated that quantitative pore space description from confocal images can be significantly influenced by imaging artifacts associated with imaging the heterogeneous and complex pore space in carbonates. By applying image deconvolution, we mitigated the confocal imaging artifacts (e.g., spherical aberration, and resolution deviation), and extracted a more reliable 3D pore-network model of the carbonate sample. We employed our optimized confocal imaging protocol to visualize and quantify macro- and micropores, and more importantly their interconnectivity within an Indiana limestone (IL) sample. The computed pore-throat size distribution (PSD) from the 3D confocal images was able to capture the inherent bimodal distribution of IL.
|Original language||English (US)|
|State||Published - Mar 27 2023|
Bibliographical noteKAUST Repository Item: Exported on 2023-04-03
Acknowledgements: We thank Prof. Volker Vahrenkamp for the fruitful discussions of the microporosity types. We thank Dr. Maxim Yutkin for his input in developing the fluorophore selection criteria. We are grateful to the Imaging and Characterization Core Laboratory team at King Abdullah University of Science and Technology (KAUST), Saudi Arabia. This project has been funded by KAUST through the baseline funding to Prof. Patzek and through the Ali I. Al-Naimi Petroleum Engineering Research Center.
ASJC Scopus subject areas
- Geotechnical Engineering and Engineering Geology