Body wave dispersion characteristics of regional deep earthquake at Southern Ryukyus subduction zone

The convergent plate boundaries known as the subduction zone is location where cold, hydrate, and old oceanic subduct under hot, dry, young continental plate. top of plate, i.e. crust usually less than 6 km thick carries hydrate material to hot mantle, which commonly an indication occurrence deep earthquake. From recent studies, regional earthquake body wave signal that occurred at was found dispersed or shown a waveguide. Thus, by examining these signals, we could further estimate characteristics zone. A narrow bandpass maximum Hilbert transform envelope are being used delay time dominant frequency energy Southern Ryukyus It has larger with 2 Hz, thus, travel within it acts low-velocity layer compared surrounding inversely high-quality (preserve high-frequency energy).