Frictional properties of Shionohira Fault Gouge, 2; A Comparison with Kuruma Fault Gouge at the southern extension of Shionohira Fault

Seshimo, Kazuyoshi ; Aoki, Kazuhiro ; Tanaka, Yukumo; Niwa, Masakazu   ; Shimamoto, Toshihiko*; Ma, S.*; Yao, L.*; Kametaka, Masao*

The April 11, 2011 Fukushima-ken Hamadori Earthquake (the largest aftershock of the 2011 off the Pacific coast of Tohoku Earthquake) formed co-seismic surface ruptures in NNW-SSE direction in Iwaki City, Fukushima Prefecture, Japan, named Shionohira Fault (hereafter called active segment). A N-S trending geological fault with lineaments (Kuruma Fault) along the southern extension of Shionohira Fault showed no surface ruptures (hereafter called non-active segment). The current report discusses differences of active and non-active segments by conducting low to high-velocity friction experiments on the gouge from shallow borehole cores.