Crust and upper-mantle structure beneath the region around the Yellow Sea from teleseismic receiver functions

Abstract

Teleseismic events are used to obtain shear-wave velocity models beneath the stations of the Yellow Sea Broadband Seismic Network (YSBSN). Some stations are located on top of either a thick sedimentary basin or highly porous volcanic rocks and receiver functions at these stations exhibit prominent high-amplitude and long-period reverberations which obscure the subtle phases associated with deeper structures. Due to the shallow subsurface effects in receiver functions, shear-wave velocity models beneath only 8 broadband seismic stations are successfully inverted. Depth to the crust-mantle transition (the Moho) varies from 30 to 38 km beneath YSBSN stations. The thickest crust is observed beneath the station JNN in China, which is attributed to the ancient collision boundary between the North China block and the South China block. Although general increase of the crustal thickness from north to south in Korea is observed with high confidence, it is not possible to delineate the location of potential collision boundary in the southern Korea peninsula, which would require wider coverage by broadband seismic instruments to resolve.