Linked Life Data

12598100

Source:http://linkedlifedata.com/resource/pubmed/id/12598100

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-4
pubmed:dateCreated
2003-2-24
pubmed:abstractText
The theoretical basis for matrix diffusion in fractured rocks and the methodology for the determination of diffusion coefficients in the laboratory are well established. One significant problem, however, remains in that it is difficult to quantify the degree of sample disturbance affecting the geometrical, geophysical and hydraulic properties of the rock matrix. A new technique, with in situ rock impregnation with resin, for examining the diffusion-accessible rock matrix has been developed and successfully adopted to the rock matrix behind a water-conducting fracture in host crystalline rocks at Nagra's Grimsel Test Site in Switzerland and JNC's Kamaishi In Situ Test Site in Japan. In line with the results of a large number of natural analogue and laboratory studies, the existence of an in situ interconnected pore network was substantiated. Matrix porosities determined on the laboratory samples from both the sites are 1.5-3 times higher than in situ values, irrespective of the technique applied. On the Grimsel granodiorite matrix, matrix porosity existing in situ and artefacts of stress release and physical disturbance, induced by sampling and sample preparation, were clearly distinguished, allowing in situ porosity to be quantified. Laboratory work with conventional techniques tends to overestimate the porosity of the rock matrix, hence leading to an overestimation of in situ matrix diffusion. The implications of these differences to a repository performance assessment are assessed with a couple of examples from existing assessments, and recommendations for future approaches to the examination of in situ matrix porosity are made.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0169-7722
pubmed:author
pubmed:copyrightInfo
Copyright 2002 Elsevier Science B.V.
pubmed:issnType
Print
pubmed:volume
61
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
131-45
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Influence of the mode of matrix porosity determination on matrix diffusion calculations.
pubmed:affiliation
JNC (Japan Nuclear Cycle Development Institute), Tono Geoscience Centre, 959-31 Jorinji, Toki, Gifu 509-5102, Japan. kunio@tono.jnc.go.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't