Crust and Uppermost Mantle Magma Plumbing System Beneath Changbaishan Intraplate Volcano, China/North Korea, Revealed by Ambient Noise Adjoint Tomography

Abstract

Changbaishan volcano (CBV), straddling the border between China and North Korea, is one of the most intriguing and explosive volcanoes on Earth owing to its voluminous Holocene eruptions and unusual magma composition within a continental intraplate setting. Despite the enormous size and destructive past, its underlying magma plumbing system remains debated and poorly understood. We present a refined high-resolution 3D crust and uppermost mantle S-wave velocity (Vs) model of CBV by applying advanced 3D full-waveform adjoint tomography on seismic ambient noise data recorded in both China and North Korea. The newly obtained seismic images detail a 3D architecture of magma plumbing systems beneath CBV, characterized by the presence of a prominent lower-crustal mush zone with an estimated melt fraction of ∼1.5%–3.6%, which is sourced from upwelling asthenosphere through a vertical narrow conduit in the uppermost mantle region that contains an estimated melt fraction of ∼6%.