High-pressure mechanical instability in rocks

J.D. Byerlee; W.F. Brace

doi:10.1126/science.164.3880.713

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High-pressure mechanical instability in rocks

J.D. Byerlee·W.F. Brace

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Abstract

At a confining pressure of a few kilobars, deformation of many sedimentary rocks, altered mafic rocks, porous volcanic rocks, and sand is ductile, in that instabilities leading to audible elastic shocks are absent. At pressures of 7 to 10 kilobars, however, unstable faulting and stick-slip in certain of these rocks was observed. This high pressure-low temperature instability might be responsible for earthquakes in deeply buried sedimentary or volcanic sequences.

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J.D. Byerlee, W.F. Brace. 1969. High-pressure mechanical instability in rocks. https://doi.org/10.1126/science.164.3880.713

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