Summary of the ASK14 Ground Motion Relation for Active Crustal Regions

Abstract

Empirical ground motion models for the average horizontal component from shallow crustal earthquakes in active tectonic regions are derived using the PEER NGA-West2 database. The model is applicable to magnitudes 3.0–8.5, distances 0–300 km, and spectral periods of 0–10 s. The model input parameters are the same as those used by Abrahamson and Silva (2008) , with the following exceptions: the loading level for nonlinear effects is based on the spectral acceleration at the period of interest rather than the PGA; and the distance scaling for hanging wall (HW) effects off the ends of the rupture includes a dependence on the source-to-site azimuth. Regional differences in large-distance attenuation and V S30 scaling between California, Japan, China, and Taiwan are included. The scaling for the HW effect is improved using constraints from numerical simulations. The standard deviation is magnitude-dependent, with smaller magnitudes leading to larger standard deviations at short periods, but smaller standard deviations at long periods. Directivity effects are not included through explicit parameters, but are captured through the variability of the empirical data.

Peak ground accelerations from large (M ≥ 7.2) shallow crustal earthquakes: a comparison with predictions from eight recent ground-motion models

“…3.3). The lowest overall bias (less than ±0.1, equivalent to ±10%) are for the models of Akkar et al (2014b, c), Abrahamson et al (2014), Bindi et al (2014a, b) and Zhao et al (2016). All models show an overall bias less than ±20%.…”

“…This reduces the total number of records to 1424 from 36 earthquakes (1969 Offshore Portugal and2006 Koryak have only a single PGA observation, which is from farther than 220 km). In general, the between-event and within-event variabilities decrease slightly (Table 2) and the absolute overall biases are less than ±10% for Akkar et al (2014b, c), Abrahamson et al (2014), Bindi et al (2014a, b), Boore et al (2014) and Campbell and Bozorgnia (2014), less than ±20% for Cauzzi et al (2015) and less than ±30% for Chiou and Youngs (2014) and Zhao et al (2016) (note the biases for these two models are slightly higher using this shorter maximum distance). More discussion of the within-and between-event variabilities is given in Sect.…”

“…The observations are compared to predictions from eight recent GMPEs that are not excluded by the criteria of Bommer et al (2010): Abrahamson et al (2014), Akkar et al (2014b, c), Bindi et al (2014a, b), Boore et al (2014), Campbell and Bozorgnia (2014), Cauzzi et al (2015), Chiou and Youngs (2014) and Zhao et al (2016). Only ground-motion models for shallow crustal earthquakes in active tectonic regimes are considered as almost all identified records come from such regions (as opposed to stable areas).…”

“…Three of the considered GMPEs include hanging wall terms (Abrahamson et al 2014;Campbell and Bozorgnia 2014;Chiou and Youngs 2014). For consistency between models and because the effect of these terms for this dataset was limited, we decided not to consider these terms for prediction.…”

“…Only ground-motion models for shallow crustal earthquakes in active tectonic regimes are considered as almost all identified records come from such regions (as opposed to stable areas). The four NGAWest2 models selected (Abrahamson et al 2014;Boore et al 2014;Campbell and Bozorgnia 2014;Chiou and Youngs 2014) are derived using predominately data from California when considering all magnitudes. For M C 7.2, however, the 1999 Chi-Chi and …”