TY - JOUR
T1 - Ground motion models for shallow crustal and deep earthquakes in Hawaii and analyses of the 2018 M 6.9 Kalapana sequence
AU - Wong, Ivan
AU - Darragh, Robert
AU - Smith, Sarah
AU - Wu, Qimin
AU - Silva, Walter
AU - Kishida, Tadahiro
N1 - Funding Information:
We extend our sincere appreciation to Morgan Moschetti of the USGS for providing us with strong motion/broadband data and to Paul Okubo, University of Hawaii, Manoa, for his assistance. Discussions with Mark Petersen, Allison Shumway, Dan McNamara, Peter Powers, and Morgan Moschetti are also appreciated. Thanks also to Claire Unruh for her assistance in the preparation of this article. Our appreciation to Editor-in-Chief David Wald, Hunter Hayes, and the Associate Editor for their assistance and to the three anonymous reviewers for their critical reviews, which improved the article. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was funded by the USGS National Earthquake Hazards Reduction Program External Program through grant G19AP00122.
Funding Information:
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was funded by the USGS National Earthquake Hazards Reduction Program External Program through grant G19AP00122.
Publisher Copyright:
© The Author(s) 2021.
PY - 2022/2
Y1 - 2022/2
N2 - The damaging 4 May 2018 M 6.9 Kalapana earthquake and its aftershocks have provided the largest suite of strong motion records ever produced for an earthquake sequence in Hawaii exceeding the number of records obtained in the deep 2006 M 6.7 Kiholo Bay earthquake. These records provided the best opportunity to understand the processes of strong ground shaking in Hawaii from shallow crustal (< 20 km) earthquakes. There were four foreshocks and more than 100 aftershocks of M 4.0 and greater recorded by the seismic stations. The mainshock produced only a modest horizontal peak ground acceleration (PGA) of 0.24 g at an epicentral distance of 21.5 km. In this study, we evaluated the 2018 strong motion data as well as previously recorded shallow crustal earthquakes on the Big Island. There are still insufficient strong motion data to develop an empirical ground motion model (GMM) and so we developed a GMM using the stochastic numerical modeling approach similar to what we had done for deep Hawaiian (>20 km) earthquakes. To provide inputs into the stochastic model, we performed an inversion to estimate kappa, stress drops, Ro, and Q(f) using the shallow crustal earthquake database. The GMM is valid from M 4.0 to 8.0 and at Joyner–Boore (RJB) distances up to 400 km. Models were developed for eight VS30 (time-averaged shear-wave velocity in the top 30 m) values corresponding to the National Earthquake Hazards Reduction Program (NEHRP) site bins: A (1500 m/s), B (1080 m/s), B/C (760 m/s), C (530 m/s), C/D (365 m/s), D (260 m/s), D/E (185 m/s), and E (150 m/s). The GMM is for PGA, peak horizontal ground velocity (PGV), and 5%-damped pseudo-spectral acceleration (SA) at 26 periods from 0.01 to 10 s. In addition, we updated our GMM for deep earthquakes (>20 km) to include the same NEHRP site bins using the same approach for the crustal earthquake GMM.
AB - The damaging 4 May 2018 M 6.9 Kalapana earthquake and its aftershocks have provided the largest suite of strong motion records ever produced for an earthquake sequence in Hawaii exceeding the number of records obtained in the deep 2006 M 6.7 Kiholo Bay earthquake. These records provided the best opportunity to understand the processes of strong ground shaking in Hawaii from shallow crustal (< 20 km) earthquakes. There were four foreshocks and more than 100 aftershocks of M 4.0 and greater recorded by the seismic stations. The mainshock produced only a modest horizontal peak ground acceleration (PGA) of 0.24 g at an epicentral distance of 21.5 km. In this study, we evaluated the 2018 strong motion data as well as previously recorded shallow crustal earthquakes on the Big Island. There are still insufficient strong motion data to develop an empirical ground motion model (GMM) and so we developed a GMM using the stochastic numerical modeling approach similar to what we had done for deep Hawaiian (>20 km) earthquakes. To provide inputs into the stochastic model, we performed an inversion to estimate kappa, stress drops, Ro, and Q(f) using the shallow crustal earthquake database. The GMM is valid from M 4.0 to 8.0 and at Joyner–Boore (RJB) distances up to 400 km. Models were developed for eight VS30 (time-averaged shear-wave velocity in the top 30 m) values corresponding to the National Earthquake Hazards Reduction Program (NEHRP) site bins: A (1500 m/s), B (1080 m/s), B/C (760 m/s), C (530 m/s), C/D (365 m/s), D (260 m/s), D/E (185 m/s), and E (150 m/s). The GMM is for PGA, peak horizontal ground velocity (PGV), and 5%-damped pseudo-spectral acceleration (SA) at 26 periods from 0.01 to 10 s. In addition, we updated our GMM for deep earthquakes (>20 km) to include the same NEHRP site bins using the same approach for the crustal earthquake GMM.
KW - Ground motion models
KW - seismic hazard
KW - stochastic point-source model
KW - stress drops
UR - http://www.scopus.com/inward/record.url?scp=85116928002&partnerID=8YFLogxK
U2 - 10.1177/87552930211044521
DO - 10.1177/87552930211044521
M3 - Article
AN - SCOPUS:85116928002
SN - 8755-2930
VL - 38
SP - 579
EP - 614
JO - Earthquake Spectra
JF - Earthquake Spectra
IS - 1
ER -