Splay fault branching along the Nankai subduction zone.
Seismic reflection profiles reveal steeply landward-dipping splay faults in the rupture area of the magnitude (M) 8.1 Tonankai earthquake in the Nankai subduction zone. These splay faults branch upward from the plate-boundary interface (that is, the subduction zone) at a depth of approximately 10 kilometers, approximately 50 to 55 kilometers landward of the trough axis, breaking through the upper crustal plate. Slip on the active splay fault may be an important mechanism that accommodates the elastic strain caused by relative plate motion.
Institute for Frontier Research on Earth Evolution, Japan Marine Science and Technology Center, Yokosuka 237-0061, Japan. jopark@jamstec.go.jp
Jin-Oh
JO
Park
Tetsuro
T
Tsuru
Shuichi
S
Kodaira
Phil R
PR
Cummins
Yoshiyuki
Y
Kaneda