Assessing Ground‐Motion Amplitudes and Attenuation for Small‐to‐Moderate Induced and Tectonic Earthquakes in the Central and Eastern United States

Abstract

In this article, we evaluate the ground-motion prediction equations (GMPEs) described by Atkinson (2015) and Shahjouei and Pezeshk (2016) with ground-motion data collected from the central and eastern United States (CEUS). The former GMPE was developed for small-to-moderate events at short hypocentral distances with application to induced earthquakes in eastern North America, using the ground-motion database developed by the Next Generation Attenuation-West2 (NGA-West2) project (Bozorgnia et al., 2014). The latter GMPE was developed for the central and eastern North America for the NGA-East project (Frankel, 2015). We compare spectral amplitudes from 46,178 ground-motion recordings at 1069 stations from 2873 earthquakes in the CEUS to the GMPEs. The ground-motion catalog is divided into potentially-induced and tectonic earthquakes using the classification scheme of Petersen et al. (2015), and their differences in geometric spreading are observed. We observe that the Atkinson (2015) GMPE is a good fit for ground motions at hypocentral distances of less than 60 km, and that the Shahjouei and Pezeshk (2016) GMPE captures the geometric spreading of ground motions at larger distances, for both induced and tectonic earthquakes.

Stress drops of induced and tectonic earthquakes in the central United States are indistinguishable

“…Because GMPEs have been developed primarily using recordings of tectonic earthquakes, the question of whether they can be applied, without modification, for predicting ground motions from induced earthquakes remains. The comparable stress drops of induced and tectonic earthquakes we find in the central United States suggest that their ground motions can be described by the same set of equations, provided that similar magnitudes, distances, and depths are considered ( 9 , 43 – 45 ). Although ground motions of earthquakes in the central and eastern United States are usually analyzed together because of a lack of data, our results support a separation of these two groups of tectonic earthquakes in the future development of GMPEs, which could be achieved by specifying the faulting style.…”

A Framework for Post-Earthquake Response Planning in Emerging Seismic Regions: An Oklahoma Case Study

“…Some responses at close distances (<20 km), which contribute the most to the seismic hazard, exceed the predicted values, indicating faster attenuation (Atkinson 2015). Similar trends have been shown for other Central and Eastern U.S. attenuation models (Gupta et al 2017), such as the model (Shahjouei and Pezeshk 2016) developed as part of the the NGA-East research project (Goulet et al 2015).…”

“…As noted in the Evaluation of Current Attenuation Models section, shallow small-to-moderate earthquakes may produce larger ground-motion amplitudes at short distances (Hough 2014, Gupta et al 2017). Due to faster attenuation, the proposed model may under-predict the response at close distances, as shown in Figure 8a.…”

A ground-motion prediction model for small-to-moderate induced earthquakes for Central and Eastern United States

“…The database of ground motions used in this study is available at https://github.com/abhineetgupta/ groundMotionsDatabase_CEUS from Gupta et al (2017)…”