HR: 1330h
AN: V12A-0569    [PDF]
TI: Three-dimensional fabric and texture analysis in granitic rocks using microfocus Xray-CT
AU: Takahashi, M
EM: takahashi-gonsuke@aist.go.jp
AF: Manabu Takahashi, Tsukuba Central 7,1-1 Higashi 1,, Tsukuba, 305-8567 Japan
AU: Noguchi, S
EM: noguson@earth.s.kanazawa-u.ac.jp
AF: Satoshi Noguchi, Kakuma-machi, Kanazawa, 920-1192 Japan
AB: Microstructure of geomaterials, which are granular sand and/or rocks, has the three-dimensional (3D) structure associated with pore, void and crack, and these structures have induced mechanical and hydrological anisotropy. In order to construct microstructure-based geomechanics for such an anisotropic geomaterials, we need the detail 3D microstructural information. Stereologically analysis is one of estimate method for 3D structure and this method can obtain geometrical properties such as orientation, density and size distribution. Recently, Takemura \& Oda (2002) have show that the geometrical property estimated by stereology is in agreement with the optical microscopic observation result using universal-stage. Stereologically method using thin section can obtain useful information about the 3D microstructure, however, it is time-consuming and tedious work. In the past decay, X-ray computed tomography (CT) is available to investigate the 3D microstructure of geomaterials (Fredrich et al., 1995; Ohtani et al., 2001). However, such a conventional X-ray CT is not enough in spatial resolution to observe individual particle and associated void in granular sand and microcrack in rock. Recently, microfocus X-ray CT was developed basis of computer technology, and this equipment can be clearly distinguished particle and microcrack even if it is a few microns in size under. In this study, we observed the 3D microstructure associated with pore and microcrack in rocks using such a microfocus X-ray CT. Using 3D image, and we can measure pore and microcrack aperture and shape under air pressure and confining pressure. Furthermore, the texture of granite expresses tensorial measurement using directional change of scanning line for reconstructed 3D image.
DE: 1744 Tectonophysics
DE: 5100 PHYSICAL PROPERTIES OF ROCKS
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting