Seismic constraints on magma evolution beneath Mount Baekdu (Changbai) volcano from transdimensional Bayesian inversion of ambient noise data

Abstract

The magmatic process of continental intraplate volcanism (CIV) is difficult to understand due to heterogeneous interactions with the crust and the lithospheric upper mantle. Mount Baekdu (Changbai) volcano (MBV) is one of the prominent CIVs in northeast Asia that has shown a complex history of eruptions and associated magmatic structures. In addition, the relationship between the crustal magmatic structures and upper mantle phenomena are enigmatic due to the lack of consistent seismic constraints for the lithospheric structure. To enhance comprehensive understanding of the MBV magma evolution, we image the lithospheric structure beneath the MBV and surrounding regions using ambient noise data and the following two approaches: (1) multiple measures of ambient noise dispersion are acquired through different methods and (2) a transdimensional Bayesian inversion method is utilized to obtain unbiased results in joint analysis of the multiple data sets. The estimated Earth structure shows a thick crust (~40 km) and a crustal anomaly with relatively high S wave velocity in the depth range 20–40 km. This type of structure extends to ~100 km north from the MBV and is accompanied by the shallow and rapid S wave velocity decrease beneath the mantle lid (~80 km). Through a comparison with previous P wave models, we interpret this structure as a consequence of compositional partitioning by mafic underplating and overlying cooled felsic layers as a result of fractional crystalization.

Imaging of Lithospheric Structure Beneath Jeju Volcanic Island by Teleseismic Traveltime Tomography

“…Decompressional melting is generated at locations with lithosphere thickness gradients induced by thermal differences or dynamic processes between the relatively thick and thin lithospheres. This mechanism has been used to explain intraplate volcanism without mantle plumes in some regions (Ballmer et al, ; Davies & Rawlinson, ; S. Kim et al, ; King & Ritsema, ; Van Wijk et al, , ). Based on our results (Figures and ) and recently improved seismological images of the lithosphere in NE Asia (see section 5.1 for references), JI is located at a transitional region of lithospheric thickness at the southern margin of the continental lithosphere beneath the Korean Peninsula and Yellow Sea.…”

“…Decompressional melting is generated at locations with lithosphere thickness gradients induced by thermal differences or dynamic processes between the relatively thick and thin lithospheres. This mechanism has been used to explain intraplate volcanism without mantle plumes in some regions Davies & Rawlinson, 2014;S. Kim et al, 2017;King & Ritsema, 2000;Van Wijk et al, 2010.…”

Intraplate Volcanism and Regional Geodynamics in NE Asia Revealed by Anisotropic Rayleigh‐Wave Tomography

“…Although many large‐scale tomographic studies commonly suggest that a deep mantle source is responsible for the intraplate volcanism (e.g., Guo et al, ; Lei & Zhao, ; Tang et al, ), debate continues about the detailed lithospheric structure related to the shallow magmatic system beneath the CBV. For example, Kim et al () imaged a middle‐lower crustal anomaly with relatively high Vs beneath the CBV, which is attributed as a consequence of compositional partitioning by mafic underplating and overlying cooled felsic layers as a result of fractional crystallization. However, Zhu et al () resolved a low‐velocity body at depths of 8–15 km under the CBV and interpreted it to be a middle crustal magma chamber, whereas the underlying lower crust is characterized by relatively high velocity that reflects cooled intrusive mafic material.…”

“…Although many large-scale tomographic studies commonly suggest that a deep mantle source is responsible for the intraplate volcanism (e.g., Guo et al, 2018;Lei & Zhao, 2005;Tang et al, 2014), debate continues about the detailed lithospheric structure related to the shallow magmatic system beneath the CBV. For example, Kim et al (2017) imaged a middle-lower crustal anomaly with relatively high Vs beneath the CBV, which is attributed as a consequence of compositional partitioning by mafic underplating and overlying cooled felsic layers as a result of fractional crystallization. However, Zhu et al Red volcano symbols denote the Late Cenozoic intraplate volcanoes (with underlying subducting slab being completely absent or deeper than 300 km as defined in Kim et al, 2016): CBV = Changbaishan volcano; JPHV = Jingpohu volcano; LGV = Longgang volcano; XJDV = Xianjingdao volcano; CRV = Chuga-Ryong volcano; ULV = Ulleung volcano; HLV = Halla volcano; FJV = Fukue-jima volcano.…”

Distribution of Partial Melt Beneath Changbaishan/Paektu Volcano, China/Democratic People's Republic of Korea

“…These studies have identified zones of low conductivity, high attenuation, or low seismic velocity, which in turn have been interpreted as indicators of partial melt and/or high temperatures in the crust beneath CMP. However, a significant limitation to these studies has been their reliance on data and observations from either China (e.g., Hetland et al, ; Kim et al, ; Wu et al, ; Wu et al, ; Zhu et al, ; Zhang et al, ) or DPRK (Kyong‐Song et al, ) but, until now, not from cross‐border experiments or integrated data sets.…”