Taiwan-specific model for V S30 prediction considering between-proxy correlations
Journal
Earthquake Spectra
Journal Volume
34
Journal Issue
4
Pages
1973-1993
Date Issued
2018
Author(s)
Abstract
Ergodic site response models are generally conditional on the time‐averaged shear wave velocity in the upper 30 m ( V S 30 ). Ground motion databases contain many recordings from Taiwan, and because of site characterization efforts, 56% of recording sites have V S 30 derived from measurements. We develop proxy‐based V S 30 prediction models, one application of which is for the remaining 44% of Taiwan sites. Our approach, which can be suitable for other regions, differs from previous studies in which proxies are based on detailed geologic categories and possible within‐category topographic gradient effects. Instead, we use three broad, age‐based geologic categories, and for the youngest category of Holocene and Quaternary undivided sediments, we propose models conditioned on gradient and elevation. We also adapt a geomorphic terrain‐based method, thus providing two V S 30 ‐prediction models. We describe a model weighting scheme that combines the models in consideration of their relative dispersions and correlation, producing a weighted mean and standard deviation natural‐log V S 30 . Included as an electronic supplement is a profile database file and a site database with site parameters for Taiwan ground motion stations.
SDGs
Type
journal article