资源环境科技发展态势分析平台

Seismic structure related to the magmatic system beneath the potentially hazardous Changbaishan volcano recently becomes hotly debated. In addition, mantle flow dynamics throughout the back-arc regions in NE Asia remain poorly constrained due to the lack of seismic data in the Korean Peninsula and surrounding ocean regions. In this study we construct a high-resolution azimuthally anisotropic Rayleigh-wave phase velocity model in NE Asia, by integrating seismic data from China, North Korea, South Korea, and Japan. The resulting isotropic velocity maps suggest possible existence of a crustal magma chamber beneath the Changbaishan volcano and that the widespread intraplate volcanism in NE Asia likely arises from the upwelling asthenosphere. The obtained anisotropic maps reveal trench-normal return flow patterns in the back-arc regions of NE Asia with local variations between East China and northeast China as controlled by the subduction geometry of the Pacific slab.