NGA‐West2 Equations for Predicting Vertical‐Component PGA, PGV, and 5%‐Damped PSA from Shallow Crustal Earthquakes

We present ground motion prediction equations (GMPEs) for computing natural log means and standard deviations of vertical‐component intensity measures (IMs) for shallow crustal earthquakes in active tectonic regions. The equations were derived from a global database with M 3.0–7.9 events. The functions are similar to those for our horizontal GMPEs. We derive equations for the primary M ‐ and distance‐dependence of peak acceleration, peak velocity, and 5%‐damped pseudo‐spectral accelerations at oscillator periods between 0.01–10 s. We observe pronounced M ‐dependent geometric spreading and region‐dependent anelastic attenuation for high‐frequency IMs. We do not observe significant region‐dependence in site amplification. Aleatory uncertainty is found to decrease with increasing magnitude; within‐event variability is independent of distance. Compared to our horizontal‐component GMPEs, attenuation rates are broadly comparable (somewhat slower geometric spreading, faster apparent anelastic attenuation), V S 30 ‐scaling is reduced, nonlinear site response is much weaker, within‐event variability is comparable, and between‐event variability is greater.