Working Group for Development and Application of Methods for Non-Ergodic Ground-Motion Models
Session: Forthcoming Updates of the USGS NSHMs: Hawaii, Conterminous U.S. and Alaska [Poster]
Type: Poster
Date: 4/28/2020
Time: 08:00 AM
Room: Ballroom
Description:
Traditionally, ground-motion models (GMMs) have been developed by combining world-wide data to have enough data to constrain the GMM. As ground-motion data sets have grown, significant regional differences in the ground motions for a given magnitude, distance and site condition have been observed. To address these regional differences, modern GMMs subdivide the global data sets into broad tectonic regions and use region-specific parameters for some of the GMM terms. Within a broad region, systematic differences in the ground-motions are also seen on the scale of 10s of km. Fine regionalization is also seen in simulations using 3-D crustal models. There is a desire to develop non-ergodic GMMs that capture this fine-scale regionalization of the ground-motion scaling.
Development of non-ergodic GMMs requires use of statistical methods different from those traditionally used in GMM development. The Non-ergodic Working Group (NEWG) was created in 2019 to investigate the statistical and scientific issues related to this new modeling approach and is co-led by the lifelines programs at the Garrick Institute and at PEER and by the applied science group from SCEC. The NEWG is an interdisciplinary multi-institutional group of about 30 individuals involved in developing GMMs. The primary goals of the working group are to (1) develop and document a suite of standard methodologies and open-source software for developing non-ergodic GMMs, which will be publicly available, (2) develop expertise in the use of these methods and (3) provide review and independent checks of the implementation of the methods. Numerical stability and run time of the estimation of hyper-parameters in a Gaussian-process regression are key issues as well as inclusion of physical constraints in the GMMs. Members of the NEWG plan to develop non-ergodic GMMs for several regions of the world over the next several years: California, Oklahoma, Chile, Colombia, Peru, Ecuador, Taiwan, Japan, France, Middle East. The non-ergodic GMMs will start to be available for use in engineering projects in 2-3 years.
Presenting Author: Grigorios Lavrentiadis
Authors
Grigorios Lavrentiadis glavrent@berkeley.edu University of California, Berkeley, Berkeley, California, United States Presenting Author
Corresponding Author
|
Norman A Abrahamson abrahamson@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Linda Al Atik linda.alatik@gmail.com Linda Alatik Consulting, San Francisco, California, United States |
Yousef Bozorgnia yousef.bozorgnia@ucla.edu University of California, Los Angeles, Los Angeles, California, United States |
Chih-Hsuan Sung karensung@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Christine A Goulet cgoulet@usc.edu Southern California Earthquake Center, Los Angeles, California, United States |
Nicholas Gregor nick@ngregor.com Nicholas Gregor Consulting, Oakland, California, United States |
Albert R Kottke arkk@pge.com Pacific Gas and Electric Company, San Francisco, California, United States |
Nicolas M Kuehn kuehn@g.ucla.edu University of California, Los Angeles, Los Angeles, California, United States |
Maxime Lacour maxlacour@berkeley.edu University of California, Berkeley, Berkeley, California, United States |
Chenying Liu cliu662@gatech.edu Georgia Institute of Technology, Atlanta, Georgia, United States |
Jogre Macedo jorge.macedo@gatech.edu Georgia Institute of Technology, Atlanta, Georgia, United States |
Xiaofeng Meng xiaofenm@usc.edu University of Southern California, Los Angeles, California, United States |
Sebastian von Specht sspecht@uni-potsdam.de University of Potsdam, Potsdam, , Germany |
Melanie Walling mwalling@geoengineers.com GeoEngineers Inc., Seattle, Washington, United States |
Kathryn E Wooddell kxwl@pge.com Pacific Gas and Electric Company, San Francisco, California, United States |
Working Group for Development and Application of Methods for Non-Ergodic Ground-Motion Models
Category
General Session