1-D velocity model for the North Korean Peninsula from Rayleigh wave dispersion of ambient noise cross-correlations

Abstract

Monitoring seismic activity in the north Korean Peninsula (NKP) is important not only for understanding the characteristics of tectonic earthquakes but also for monitoring anthropogenic seismic events. To more effectively investigate seismic properties, reliable seismic velocity models are essential. However, the seismic velocity structures of the region have not been well constrained due to a lack of available seismic data. This study presents 1-D velocity models for both the inland and offshore (western East Sea) of the NKP. We constrained the models based on the results of a Bayesian inversion process using Rayleigh wave dispersion data, which were measured from ambient noise cross-correlations between stations in the southern Korean Peninsula and northeast China. The proposed models were evaluated by performing full moment tensor inversion for the 2013 Democratic People’s Republic of Korea (DPRK) nuclear test. Using the composite model consisting of both inland and offshore models resulted in consistently higher goodness of fit to observed waveforms than previous models. This indicates that seismic monitoring can be improved by using the proposed models, which resolve propagation effects along different paths in the NKP region.

Terrain Proxy-Based Site Classification for Seismic Zonation in North Korea within a Geospatial Data-Driven Workflow

“…During SVR, we attempted to match the error under any threshold. The former condition generates the objective function in equation (Min 1 2 w 2 ) where the size of the normal vector to the surface is approximated.…”

“…However, assessing the seismic hazards is challenging because of the lack of and/or discrepancies in the data from public seismic stations, damage inventories of earthquakes, and site investigation results. Historically, the largest earthquake (M W 6.2;19 March 1952) in the Korean Peninsula occurred near Pyongyang, North Korea [1]. Moreover, nuclear tests between 2006 and 2017 triggered events such as mine collapses [2].…”

Multiple Rayleigh waves guided by the planar surface of a continuously twisted structurally chiral material

“…Elastodynamic surface waves [ 1 , 2 ] have been studied from the 1880s, when Rayleigh [ 3 ] hinted at their significance for earthquakes, which was subsequently borne out both experimentally and theoretically [ 4 – 6 ]. Seismological applications of surface waves [ 7 ] include the detection of subsurface anomalies such as tunnels [ 8 ] and mineral deposits [ 9 ] as well as investigations of the evolution of planetary crusts [ 10 , 11 ]. Current applications in materials science include the non-destructive testing of polycrystalline materials [ 12 ] such as silicon for solar cells [ 13 ].…”