6:15 PM - 7:30 PM
[SSS28-P21] High-resolution Multi-Channel Sonic survey on the seaward extension of the Kokura-Higashi Faults
Keywords:Kokura-Higashi Faults, multi-channel sonic survey, strike-slip fault, Hibiki-nada
The Kokura-Higashi Faults are NNE-SSW trending left lateral strike-slip fault. It is recognized obviously the Kokura-Higashi Faults are distributing from Kokura-Kita to Kokura-Minami ward, Fukuoka Prefecture. However, the Headquarters for Earthquake Research Promotion (2013) pointed that the northern extent of the faults could reach to off Hikoshima, Hibiki-nada, based on the distribution of steep gravity gradient zone in the northern Kyushu. We have conducted a high-resolution multi-channel sonic survey using Boomer source and 12-channel, 2.5-m-channel-interval streamer to clarify the precise fault distribution and structure in Hibiki-nada. The acoustic profiles imaged several faults that deform shallow strata.