Experimental evidence for different strain regimes
of crack populations in a clay model
Spyropoulos C, Griffith WJ, Scholz CH, Shaw BE
GEOPHYSICAL RESEARCH LETTERS
26: (8) 1081-1084 APR 15 1999
Abstract:
We report results from clay extension experiments used
as a model for the evolution of fault populations due to stress interactions.
At yielding cracks begin to appear and the brittle strain due to them quickly
reaches a rate matching the applied stretching rate. The crack density
(number of cracks per unit area) initially increases apace, then reaches
a maximum at a critical strain, decreasing thereafter. At low strains,
where the crack population is dilute, a power law length distribution is
observed, which at high strain, gradually transitions to an exponential.
This agrees with fault populations data observed in low and high strain
settings. These results indicate that fault populations ranging from power
law to exponential size-frequency distributions reflect the population
evolution with increased strain.