11:30 AM - 11:45 AM
[SCG58-10] Possible fluid effects on megathrust fault in the coseismic rupture zone of the 2011 Tohoku-oki earthquake
Keywords:tectonic structure, rupture zone, fluid
In order to estimate a possible fluid influence on accreted structure landward of the Japan Trench, we processed and analyzed multichannel seismic (MCS) reflection data that extend across the forearc slope of the Japan Trench. Preliminary MCS results show a wedge-shaped unit under the upper slope, a strong reflection zone overlying a prominent reflector with reverse polarity under the middle slope, indicating the possible effects of fluid on the megathrust fault. A comparison between post-stack time migrated profile and pre-stack depth migrated profile demonstrates the tectonic structures suggesting the fluid distribution.