An Empirical Model for the Interfrequency Correlation of Epsilon for Fourier Amplitude Spectra

Abstract

Research Article| May 07, 2019 An Empirical Model for the Interfrequency Correlation of Epsilon for Fourier Amplitude Spectra Jeff Bayless; Jeff Bayless Corresponding Author aDepartment of Civil and Environmental Engineering, University of California, Davis, 3021 Ghausi Hall, One Shields Avenue, Davis, California 95616 U.S.A., jrbayless@ucdavis.edu Search for other works by this author on: GSW Google Scholar Norman A. Abrahamson Norman A. Abrahamson aDepartment of Civil and Environmental Engineering, University of California, Davis, 3021 Ghausi Hall, One Shields Avenue, Davis, California 95616 U.S.A., jrbayless@ucdavis.edu Search for other works by this author on: GSW Google Scholar Bulletin of the Seismological Society of America (2019) 109 (3): 1058–1070. https://doi.org/10.1785/0120180238 Article history first online: 07 May 2019 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Jeff Bayless, Norman A. Abrahamson; An Empirical Model for the Interfrequency Correlation of Epsilon for Fourier Amplitude Spectra. Bulletin of the Seismological Society of America 2019;; 109 (3): 1058–1070. doi: https://doi.org/10.1785/0120180238 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract An empirical ground‐motion model (GMM) is presented for the interfrequency correlation of normalized residuals, epsilon (⁠ε⁠), for smoothed Fourier amplitude spectra (FAS). The interfrequency correlation of ε (⁠ρε⁠) model is developed for the smoothed effective amplitude spectrum (EAS), as defined by Pacific Earthquake Engineering Research Center (PEER; Goulet et al., 2018). The EAS is the orientation‐independent horizontal‐component FAS of ground acceleration. Ground‐motion data are from the PEER Next Generation Attenuation‐West2 database (Ancheta et al., 2014), which includes shallow crustal earthquakes in active tectonic regions. The normalized residuals are obtained from the Bayless and Abrahamson (2018b) GMM and are partitioned into between‐event, between‐site, and within‐site components, and a model is developed for the total correlation between frequencies. The total correlation model features a two‐term exponential decay with the natural logarithm of frequency. At higher frequencies, the model differs substantially from previously published models, in which the ground‐motion smoothing technique used has a large effect on the resulting correlations. The empirical ρε is not found to have statistically significant magnitude, distance, site parameter, or regional dependence, although potential regional variations should be studied further. The model is applicable for crustal earthquakes in active tectonic regions worldwide, for rupture distances of 0–300 km, M 3.0–8.0, and over the frequency range 0.1–24 Hz. Tables for the total correlation model coefficients and covariance matrices are provided in the Ⓔ supplemental content to this article. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.