Thermo-Poro-Mechanical Properties of Clayey Gouge and Application to Rapid Fault Shearing
نویسندگان
چکیده
In this paper, the mechanism of fault pressurization in rapid slip events is analyzed on the basis of a complete characterization of the thermo-poro-mechanical behavior of a clayey gouge extracted at 760m depth in Aigion fault in the active seismic zone of the Gulf of Corinth, Greece. It is shown that the thermally collapsible character of this clayey gouge can be responsible for a dramatic reduction of effective stress and a full fluidization of the material. The thickness of the ‘ultra localized’ zone of highly strained material is a key parameter that controls the competing phenomena of pore pressure increase leading to fluidization of the fault gouge and temperature increase leading to pore fluid vaporization. Published in: Int. J. Numer. Anal. Meth. Geomech., 2007; 31:523–540
منابع مشابه
Stress orientation evaluated from strain localisation analysis in Aigion fault
Within the frame of the ‘CRL’ (Corinth Rift Laboratory project) (Cornet et al, 2004a) centered on the south western sector of the Gulf of Corinth (http://www.corinth-rift-lab.org), fault zone cores from the active Aigion fault have been collected continuously from depths between 708 m to 782 m. Inside this clayey core, a clear shearing surface with marked slip lines is visible on a plane that m...
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