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Diffusion Porosity and Diffusivity of Radionuclides In Granitic Rocks. Part I: Diffusion Interfaces Around Permeable Fractures

Published online by Cambridge University Press:  28 February 2011

Veijo O. Pirhonen
Affiliation:
Technical Research Centre of Finland, Geotechnical Laboratory, P.O. BOX 108, SF-02151 Espoo, Finland
K. Front
Affiliation:
Technical Research Centre of Finland, Geotechnical Laboratory, P.O. BOX 108, SF-02151 Espoo, Finland
P. Pitkänen
Affiliation:
Technical Research Centre of Finland, Geotechnical Laboratory, P.O. BOX 108, SF-02151 Espoo, Finland
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Abstract

This paper addresses the problem of evaluation of radionuclide retardation in fractured rocks. Pore space around permeable fractures was examined by means of the fracture profiling technique which comprises porosity measurements and chemical analyses along the profiles perpendicular to the fracture surfaces.

Scanning electron micrographs show that the examined interfaces contain microfractures and tube-like diffusion channels. These are most frequent within 2 - 4 cm from the surface of the examined fractures. Porosity and chemistry of these interfaces are fracture specific. It is possible that diffusion into the rock matrix is restricted into the interfaces around the permeable fractures.

Type
Research Article
Copyright
Copyright © Materials Research Society 1991

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References

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