[SSS11-P05] Crustal Structure in and around Senoumi Bank, Suruga Bay, Central Japan as Derived from Seismic Refraction Survey
Keywords:Tokai Earthquake, Suruga Bay, Earthquake Activity, Crustal Structure
In November of 2016, we carried out seismic refraction measurement(Tsuruga et al., 2017) using airgun and 6-OBS’s, and we conducted the survey by research vessel “Shinyomau” of Tokyo University of Marine Science and Technology which was renewed on 2016.
The analysis of these refraction data, using the two-dimensional ray tracing method of trial sought detailed crustal structure model.In this report, we show the crustal structure model in and around Senoumi Bank, Suruga Bay .
The features of the crustal structure model thus obtained are as follows;
Sedimentary layers are shown by seismic reflection profiles (Tsuruga et al., 2017) .The thickness of the layers along the seabed undulations in approximately 0.4 km.
Second-layers are 2.9 km / sec. This makes interpreting the sedimentary layer 2. This layer is thinner in the center of the line, thicker at both ends positioning line.
Third-Layers are acoustic basement of 4.7 km / sec. Western slope of Senoumi Bank are became thin layer.
4th-Layers are 5.1 km / sec. This layer is considered the top of the continental crust.
Our result could not find a granitic layer, but depth was confirmed the structure of up to 8 km.