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	<journal>
		<journal_title>eEarth Discussions</journal_title>
		<journal_url>www.electronic-earth-discuss.net</journal_url>
		<issn>1815-3836</issn>
		<eissn>1815-3844</eissn>
		<volume_number>4</volume_number>
		<issue_number>1</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/eed-4-1-2009</doi>
	<article_url>http://www.electronic-earth-discuss.net/4/1/2009/</article_url>
	<abstract_html>http://www.electronic-earth-discuss.net/4/1/2009/eed-4-1-2009.html</abstract_html>
	<fulltext_pdf>http://www.electronic-earth-discuss.net/4/1/2009/eed-4-1-2009.pdf</fulltext_pdf>
	<start_page>1</start_page>
	<end_page>19</end_page>
	<publication_date>2009-02-03</publication_date>
	<article_title content_type="html">Morphology of the pore space in claystones – evidence from BIB/FIB ion beam sectioning and cryo-SEM observations</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>G. Desbois</name>
			<email>g.desbois@ged.rwth-aachen.de</email>
		</author>
		<author numeration="2" affiliations="1">
			<name>J. L. Urai</name>
		</author>
		<author numeration="3" affiliations="2">
			<name>P. A. Kukla</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Geologie – Endogene Dynamik, RWTH Aachen University, Lochnerstr. 4–20, 52062 Aachen, Germany</affiliation>
		<affiliation numeration="2" content_type="html">Geological Institute, RWTH Aachen University, Wüllnerstr. 2, 2062 Aachen, Germany</affiliation>
	</affiliations>
	<abstract content_type="html">The morphology of pore space has a strong effect on mechanical and transport
properties of mudrocks and clay-rich fault gouge, but its characterization
has been mostly indirect. We report on a study of Boom clay from a proposed
disposal site of radioactive waste (Mol site, Belgium) using high resolution
SEM at cryogenic temperature, with ion beam cutting to prepare smooth,
damage free surfaces. Pores commonly have crack-like tips, preferred
orientation parallel to bedding and power law size distribution. We define a
number of pore types depending on shape and location in the microstructure:
large jagged pores in strain shadows of clastic grains, high aspect ratio
pores between similarly oriented phyllosilicate grains and crescent-shaped
pores in saddle reefs of folded phyllosilicates. 3-D reconstruction by serial
sectioning shows 3-D connectivity of the pore space. These findings call for
reinterpretation of traditional pore size distributions calculated from
mercury Injection experiments, explain slaking of clays by successive
wetting and drying and provide the basis for microstructure-based models of
transport in clays.</abstract>
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</article>

