TY  - JOUR
A1  - Weatherill, Graeme
A1  - Kotha, Sreeram Reddy
A1  - Cotton, Fabrice Pierre
T1  - Re-thinking site amplification in regional seismic risk assessment
JF  - Earthquake spectra : the professional journal of the Earthquake Engineering Research Institute
N2  - Probabilistic assessment of seismic hazard and risk over a geographical region presents the modeler with challenges in the characterization of the site amplification that are not present in site-specific assessment. Using site-to-site residuals from a ground motion model fit to observations from the Japanese KiK-net database, correlations between measured local amplifications and mappable proxies such as topographic slope and geology are explored. These are used subsequently to develop empirical models describing amplification as a direct function of slope, conditional upon geological period. These correlations also demonstrate the limitations of inferring 30-m shearwave velocity from slope and applying them directly into ground motion models. Instead, they illustrate the feasibility of deriving spectral acceleration amplification factors directly from sets of observed records, which are calibrated to parameters that can be mapped uniformly on a regional scale. The result is a geologically calibrated amplification model that can be incorporated into national and regional seismic hazard and risk assessment, ensuring that the corresponding total aleatory variability reflects the predictive capability of the mapped site proxy.
KW  - earthquake hazard analysis
KW  - ground motion
KW  - seismic risk
KW  - site effects
KW  - regional mapping
Y1  - 2020
U6  - https://doi.org/10.1177/8755293019899956
SN  - 8755-2930
SN  - 1944-8201
VL  - 36
IS  - 1_SUPPL
SP  - 274
EP  - 297
PB  - Sage Publishing
CY  - Thousand Oaks, CA
ER  -