Publication Date:
2019
Description:
Abstract
There is a growing concern about the potential eruption of the Changbaishan volcano (CBV) in recent years, but the magmatic system beneath this volcano remains hotly debated. In this study, we construct a high‐resolution 3‐D crust and upper mantle S wave velocity (Vs) model beneath the CBV and adjacent regions combining ambient noise and earthquake surface wave tomography. Distinct low Vs anomalies are revealed in the crust and upper mantle beneath the CBV. The middle‐lower crustal low‐velocity body is interpreted to be the main magma chamber that may feed the surface volcanism and hydrothermal activities. The upper mantle low‐velocity zone is representative of upwelling asthenosphere. The lower crust beneath the Longgang volcano and Jingpohu volcano is also characterized by low Vs anomalies, maybe indicating low‐degree partial melting. We propose that the intraplate volcanism of the CBV as well as the Longgang volcano and Jingpohu volcano is driven by the decompression melting of upwelling asthenosphere, which could originate from the mantle transition zone as suggested by previous large‐scale tomographic studies. Moreover, the geologically identified Solonker‐Xar Moron‐Changchun‐Yanji suture zone is delineated by a prominent high Vs anomaly in the uppermost mantle, which may be explained by the fossil slab remnants or deformational fabrics resulted from the final closure of the Paleo‐Asian Ocean in the Late Paleozoic to Early Mesozoic.
Print ISSN:
2169-9313
Electronic ISSN:
2169-9356
Topics:
Geosciences
,
Physics
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