PEER has just published Report No. 2020/07: "Comparison of NGA-Sub Ground-Motion Models." It was authored by Nicholas Gregor, Consultant; Kofi Addo, BC Hydro; Linda Al Atik, Consultant; Gail M. Atkinson, University of Western Ontario; David M. Boore, Geophysicist; Yousef Bozorgnia, University of California, Los Angeles; Kenneth W. Campbell, Core Logic; Brian S.-J. Chiou, California Department of Transportation; Zeynep Gülerce, Middle East Technical University; Behzad Hassani, BC Hydro; Tadahiro Kishida, Khalifa University of Science and Technology; Nico Kuehn, University of California, Los Angeles; Saburoh Midorikawa, Tokyo Institute of Technology; Silvia Mazzoni, University of California, Los Angeles; Grace A. Parker, University of California, Los Angeles (Now at the U.S. Geological Survey, Moffett Field, California); Hongjun Si, Seismological Research Institute Inc.; Jonathan P. Stewart, University of California, Los Angeles; Robert R. Youngs, Wood Environmental and Infrastructure Solutions, Inc.
Ground-motion models (GMMs) for subduction earthquakes recently developed as part of the NGA-Subduction (NGA-Sub) project are compared in this report. The three models presented in this comparison report are documented in their respective PEER reports. Two of the models are developed for a global version and as well regionalized models. The third model is developed based on earthquakes contain in the NGA-Sub dataset only from Japan and as such is applicable for Japan. As part of the comparisons presented in this report, deterministic calculations are provided for the global and regional cases amongst the models. The digital values and additional plots from these deterministic comparisons are provided as part of the electronic supplement for this report. In addition, ground-motion estimates are provided for currently published subduction GMMs. Two example probabilistic seismic hazard analysis calculations are also presented for two sites located in the Pacific Northwest Region in the state of Washington. Based on the limited comparisons presented in this report, a general understanding of these new GMMs can be appreciated with the expectation that the implementation for a specific seismic hazard study should incorporate similar and additional comparisons and sensitivity studies similar to the ones presented in this report.