A global hybrid VS30 map with a topographic slope–based default and regional map insets
Time-averaged shear wave velocity over the upper 30 m of the earth’s surface (VS30) is a key parameter for estimating ground motion amplification as both a predictive and a diagnostic tool for earthquake hazards. The first-order approximation of VS30 is commonly obtained through a topographic slope–based or terrain proxy due to the widely available nature of digital elevation models. However, better-constrained VS30 maps have been developed in many regions. Such maps preferentially employ various combinations of VS30 measurements, higher-resolution elevation models, lithologic, geologic, geomorphic, and other proxies and often utilize refined interpolation schemes. We develop a new hybrid global VS30 map database that defaults to the global slope-based VS30 map, but smoothly inserts regional VS30 maps where available. In addition, we present comparisons of the default slope-based proxy maps against the new hybrid version in terms of VS30 and amplification ratio maps, and uncertainties in assigned VS30 values.
Citation Information
Publication Year | 2020 |
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Title | A global hybrid VS30 map with a topographic slope–based default and regional map insets |
DOI | 10.1177/8755293020911137 |
Authors | David C. Heath, David J. Wald, C. Bruce Worden, Eric M. Thompson, Gregory M. Smoczyk |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Earthquake Spectra |
Index ID | 70211979 |
Record Source | USGS Publications Warehouse |
USGS Organization | Geologic Hazards Science Center |