TY - JOUR
T1 - Fractal particle size distribution of pulverized fault rocks as a function of distance from the fault core
AU - Muto, Jun
AU - Nakatani, Tsurugi
AU - Nishikawa, Osamu
AU - Nagahama, Hiroyuki
N1 - Publisher Copyright:
©2015. American Geophysical Union. All Rights Reserved.
PY - 2015/5/28
Y1 - 2015/5/28
N2 - The size distributions of particle in pulverized rocks from the San Andreas fault and the Arima-Takatsuki Tectonic Line were measured. The rocks are characterized by the development of opening mode fractures with an apparent lack of shear. Fragments in the rocks in both fault zones show a fractal size distribution down to the micron scale. Fractal dimensions, dependent on mineral type, decrease from 2.92 to 1.97 with increasing distance normal to the fault core. The fractal dimensions of the rocks are higher than those of both natural and experimentally created fault gouges measured in previous studies. Moreover, the dimensions are higher than the theoretically estimated upper fractal limit under confined comminution. Dimensions close to 3.0 have been reported in impact loading experiments. The observed characteristics indicate that pulverization is likely to have occurred by a dynamic stress pulse with instantaneous volumetric expansion, possibly during seismic rupture propagation similar to impact loading.
AB - The size distributions of particle in pulverized rocks from the San Andreas fault and the Arima-Takatsuki Tectonic Line were measured. The rocks are characterized by the development of opening mode fractures with an apparent lack of shear. Fragments in the rocks in both fault zones show a fractal size distribution down to the micron scale. Fractal dimensions, dependent on mineral type, decrease from 2.92 to 1.97 with increasing distance normal to the fault core. The fractal dimensions of the rocks are higher than those of both natural and experimentally created fault gouges measured in previous studies. Moreover, the dimensions are higher than the theoretically estimated upper fractal limit under confined comminution. Dimensions close to 3.0 have been reported in impact loading experiments. The observed characteristics indicate that pulverization is likely to have occurred by a dynamic stress pulse with instantaneous volumetric expansion, possibly during seismic rupture propagation similar to impact loading.
KW - Arima-Takatsuki Tectonic Line
KW - San Andreas fault
KW - dynamic stress pulse
KW - fractal
KW - particle size distribution
KW - pulverized rocks
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U2 - 10.1002/2015GL064026
DO - 10.1002/2015GL064026
M3 - Article
AN - SCOPUS:84931565705
VL - 42
SP - 3811
EP - 3819
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 10
ER -