Roughness of stylolites: a stress-induced instability with non local interactions

J. Schmittbuhl; F. Renard; J. P. Gratier

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Roughness of stylolites: a stress-induced instability with non local interactions

J. Schmittbuhl·F. Renard·J. P. Gratier

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Abstract

We study the roughness of stylolite surfaces (i.e. natural pressure-dissolution surfaces in sedimentary rocks) from profiler measurements at laboratory scales. The roughness is shown to be nicely described by a self-affine scaling invariance. At large scales, the roughness exponent is $ζ_1 \approx 0.5$ and very different from that at small scales where $ζ_2 \approx 1.1$. A cross-over length scale at around $λ_c =1$mm is well characterized and interpreted as a possible fossil stress measurement if related to the Asaro-Tiller-Grinfeld stress-induced instability. Measurements are consistent with a Langevin equation that describes the growth of stylolite surfaces in a quenched disordered material with long range elastic correlations.

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J. Schmittbuhl, F. Renard, J. P. Gratier. 2003-03-04. Roughness of stylolites: a stress-induced instability with non local interactions. https://arxiv.org/abs/cond-mat/0303057

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