Use of Geostatistics For Accurate Mapping of Earthquake Ground Motion

Abstract

The geostatistical method of kriging is applied for the analysis, estimation and mapping of earthquake ground motion. No modification to this method was required for this new application. Along with kriging, the concept of the semi-variogram is introduced and shown to be important for estimation and mapping. In geostatistical analyses of earthquake ground motion the ground motion is modelled by a random function. This random function model is shown to be accurate for providing estimates of earthquake ground motion at unsampled locations. Kriging is applied in this paper for the mapping of peak horizontal acceleration recorded during the 1971 San Fernando, and the 1983 Coalinga, California earthquakes. These results are compared to maps predicted using attenuation expressions and differences are analysed. Results demonstrate the utility of kriging for the analysis of earthquake ground motion.