| Publication type: | Article in scientific journal |
| Type of review: | Peer review (publication) |
| Title: | 3D geometry and topology of pore pathways in Opalinus clay : implications for mass transport |
| Authors: | Keller, Lukas Holzer, Lorenz Wepf, Roger Gasser, Philippe |
| DOI: | 10.1016/j.clay.2011.02.003 |
| Published in: | Applied Clay Science |
| Volume(Issue): | 52 |
| Issue: | 1-2 |
| Page(s): | 85 |
| Pages to: | 95 |
| Issue Date: | Apr-2011 |
| Publisher / Ed. Institution: | Elsevier |
| ISSN: | 0169-1317 |
| Language: | English |
| Subjects: | Map |
| Subject (DDC): | 620.11: Engineering materials |
| Abstract: | Clay-rich sedimentary rocks are considered as seal lithologies for hosting radioactive waste or as caprocks for geological carbon sequestration sites. Evaluation of the rock's sealing capacity requires a comprehensive understanding of mass transport processes, which, in turn, demands knowledge of the 3D structure of pore space. Here, the use of focused ion beam nanotomography (FIB-nt) in building realistic pore space models is demonstrated along with a novel approach employed to analyze the topology of the pore space. The method was applied to three samples of the Opalinus clay of in northern Switzerland which is considered as a candidate host rock formation for the disposal of radioactive waste. Due to resolution limitations the lower limit of analyzed pore radii was about 10 nm. Pore radii > 10 nm were related to a physical porosity of about 2 vol.%. Comparing the pore size distribution determined by FIB-nt with the one obtained by N2 adsorption analysis, FIB-nt revealed the structure of about 20% of the total pore space. The total external porosity determined by N2 adsorption analysis was in the range of 10 to 12 vol.%. Our approach to analyze the complex 3D structure of the pore space was based on converting the voxel based 3D structure into a 3D graph of the pore skeleton. A 3D graph representation permitted determination of the spatial distribution of pore space geometrical properties such as pore path orientation, pore path tortuosity and pore path length. Pore-paths in Opalinus clay show a preferred orientation within the bedding plane in combination with a comparatively low pore path tortuosity. Pore path tortuosity perpendicular to the bedding plane is higher by a factor of as much as five. Anisotropy in pore space is caused by spatial density variations of pore path orientation (i.e. preferred orientations of pore paths) in combination with an elongated pore shape (i.e. low tortuosity). |
| URI: | https://digitalcollection.zhaw.ch/handle/11475/2199 |
| Fulltext version: | Published version |
| License (according to publishing contract): | Licence according to publishing contract |
| Departement: | School of Engineering |
| Organisational Unit: | Institute of Computational Physics (ICP) |
| Appears in collections: | Publikationen School of Engineering |
Files in This Item:
There are no files associated with this item.
Show full item record
Keller, L., Holzer, L., Wepf, R., & Gasser, P. (2011). 3D geometry and topology of pore pathways in Opalinus clay : implications for mass transport. Applied Clay Science, 52(1-2), 85–95. https://doi.org/10.1016/j.clay.2011.02.003
Keller, L. et al. (2011) ‘3D geometry and topology of pore pathways in Opalinus clay : implications for mass transport’, Applied Clay Science, 52(1-2), pp. 85–95. Available at: https://doi.org/10.1016/j.clay.2011.02.003.
L. Keller, L. Holzer, R. Wepf, and P. Gasser, “3D geometry and topology of pore pathways in Opalinus clay : implications for mass transport,” Applied Clay Science, vol. 52, no. 1-2, pp. 85–95, Apr. 2011, doi: 10.1016/j.clay.2011.02.003.
KELLER, Lukas, Lorenz HOLZER, Roger WEPF und Philippe GASSER, 2011. 3D geometry and topology of pore pathways in Opalinus clay : implications for mass transport. Applied Clay Science. April 2011. Bd. 52, Nr. 1-2, S. 85–95. DOI 10.1016/j.clay.2011.02.003
Keller, Lukas, Lorenz Holzer, Roger Wepf, and Philippe Gasser. 2011. “3D Geometry and Topology of Pore Pathways in Opalinus Clay : Implications for Mass Transport.” Applied Clay Science 52 (1-2): 85–95. https://doi.org/10.1016/j.clay.2011.02.003.
Keller, Lukas, et al. “3D Geometry and Topology of Pore Pathways in Opalinus Clay : Implications for Mass Transport.” Applied Clay Science, vol. 52, no. 1-2, Apr. 2011, pp. 85–95, https://doi.org/10.1016/j.clay.2011.02.003.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.