NGA-West2 Ground Motion Model for the Average Horizontal Components of PGA, PGV, and 5% Damped Linear Acceleration Response Spectra

Abstract

We used an expanded PEER NGA-West2 database to develop a new ground motion prediction equation (GMPE) for the average horizontal components of PGA, PGV, and 5% damped linear pseudo-absolute acceleration response spectra at 21 periods ranging from 0.01 s to 10 s. In addition to those terms included in our now superseded 2008 GMPE, we include a more-detailed hanging wall model, scaling with hypocentral depth and fault dip, regionally independent geometric attenuation, regionally dependent anelastic attenuation and site conditions, and magnitude-dependent aleatory variability. The NGA-West2 database provides better constraints on magnitude scaling and attenuation of small-magnitude earthquakes, where our 2008 GMPE was known to be biased. We consider our new GMPE to be valid for estimating horizontal ground motion from shallow crustal continental earthquakes in an active tectonic domain for rupture distances ranging from 0 km to 300 km and magnitudes ranging from 3.3 to 7.5–8.5, depending on source mechanism.

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

“…6) allows the magnitude-scaling of the GMPEs to be tested. The magnitude scaling of five of the models (Abrahamson et al 2014;Boore et al 2014;Campbell and Bozorgnia 2014;Cauzzi et al 2015;Chiou and Youngs 2014) is valid for these data, with no clear trends. The two RESORCE models (Akkar et al 2014b, c;Bindi et al 2014a, b) show slight overprediction for M [ 7.6; neither model was derived using any data from such events.…”

“…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 …”