← Back to Gallery

Development of the Korean Peninsula VS30 Map Based on Terrain Classification Derived from DEM

The national seismic intensity service in South Korea provided by Korea Meteorological Administration (KMA) has used the ShakeMap (Wald et al., 2006) that uses V_S30 as a main site variable characterizing the site amplification (KMA, 2018). The V_S30 is estimated from geophysical exploration. However, it is practically impossible to conduct geophysical exploration at the entire area of the Korean Peninsula. Therefore, the KMA has used the V_S30 map (Choi et al., 2022) developed using proxies such as slope gradient and geologic layers for the input site variable in the ShakeMap.

In addition to the geologic based V_S30 map, this study suggests a new V_S30 map using topographic parameters such as slope gradient, surface texture and local convexity. Surface texture is a measure of spatial intricacy representing a change in sign of slope aspect or curvature per unit area. Local convexity is introduced to distinguish low-relief features such as alluvial fans. In previous studies, the land was classified into 16 terrain classes using these three variables (Iwahashi and Pike, 2007) and terrain-class-based V_S30 schemes were suggested (Yong et al., 2012). Per Iwahashi and Pike (2007), classifying terrain depends on the target region. Each class is defined by dividing the range of slope gradient, surface texture or local convexity by half. Therefore, there are different criteria based on the target region and resolution, and Iwahashi and Pike (2007) suggest different criteria for World, Japan and Shimukappu regions. This study targets the Korean Peninsula. A terrain classification map according to the Iwahashi and Pike (2007) method is created, and the optimal V_S30 for each terrain class is suggested using 11,260 estimated V_S30s in the Korean Peninsula. This new V_S30 map that is not based on the geologic map can be used to reduce the uncertainty of V_S30 prediction by combining with the geologic-based V_S30 map.

Session: Earthquakes in the Urban Environment [Poster]

Type: Poster

Room: Evergreen Ballroom

Date: 4/22/2022

Presentation Time: 08:00 AM Pacific

Presenting Author: Inhyeok Choi

Student Presenter: Yes

Additional Authors