Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR Data

The June 23 2020 Oaxaca Mw 7.4 interplate thrust earthquake struck the state of Oaxaca in Mexico, generating strong shaking and a long-lived tsunami. This earthquake is well recorded by the teleseismic, high-rate Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) da...

Full description

Bibliographic Details
Main Authors: Guisen Wen, Xingxing Li, Yingwen Zhao, Caijun Xu, Guangyu Xu
Format: Article
Language:English
Published: Frontiers Media S.A. 2022-07-01
Series:Frontiers in Earth Science
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/feart.2022.951033/full
_version_ 1811287664697016320
author Guisen Wen
Xingxing Li
Yingwen Zhao
Caijun Xu
Guangyu Xu
author_facet Guisen Wen
Xingxing Li
Yingwen Zhao
Caijun Xu
Guangyu Xu
author_sort Guisen Wen
collection DOAJ
description The June 23 2020 Oaxaca Mw 7.4 interplate thrust earthquake struck the state of Oaxaca in Mexico, generating strong shaking and a long-lived tsunami. This earthquake is well recorded by the teleseismic, high-rate Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data, which provides an opportunity to understand the rupture characteristics of the Mexican subduction zone. Here, an integrated inversion strategy involving centroid moment tensor inversion and kinematic finite-fault inversion is used to study the rupture history of the 2020 Oaxaca earthquake. The fault geometry and source duration time derived from the centroid moment tensor solution are used as prior information in linear kinematic finite-fault joint inversion. The rupture initial point and relative weight of each dataset are determined to estimate a well-constrained rupture model. The finite-fault model shows the rupture expanded bilaterally around the hypocenter, the peak slip is 3.5 m, the main slip was located at a depth of 15–30 km, the whole rupture lasted about 20 s, and a 95% moment rate was released at 15 s. The half-duration of the finite-fault inversion is consistent with the centroid moment tensor inversion results (half-duration 9 s), which shows the good resolution of the temporal information. The total scalar moment was 1.5 × 1020 Nm, equivalent to a moment magnitude of Mw 7.4. The integrated inversion strategy used in this study is useful since the prior information can be derived and used to constrain the rupture process. Both the centroid moment tensor and finite-fault inversion mainly rely on identical temporal information provided by teleseismic P waveforms. The 2020 Oaxaca earthquake was mainly the interaction between Cocos and the North American plate, and the slow slip events may be the key factor affecting the seismogenic zone width in the Oaxaca region.
first_indexed 2024-04-13T03:23:19Z
format Article
id doaj.art-0f8b1c2bfa954213b5139773cb954324
institution Directory Open Access Journal
issn 2296-6463
language English
last_indexed 2024-04-13T03:23:19Z
publishDate 2022-07-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Earth Science
spelling doaj.art-0f8b1c2bfa954213b5139773cb9543242022-12-22T03:04:43ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632022-07-011010.3389/feart.2022.951033951033Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR DataGuisen Wen0Xingxing Li1Yingwen Zhao2Caijun Xu3Guangyu Xu4School of Geodesy and Geomatics, Wuhan University, Wuhan, ChinaSchool of Geodesy and Geomatics, Wuhan University, Wuhan, ChinaSchool of Geodesy and Geomatics, Wuhan University, Wuhan, ChinaSchool of Geodesy and Geomatics, Wuhan University, Wuhan, ChinaFaculty of Geomatics, East China University of Technology, Nanchang, ChinaThe June 23 2020 Oaxaca Mw 7.4 interplate thrust earthquake struck the state of Oaxaca in Mexico, generating strong shaking and a long-lived tsunami. This earthquake is well recorded by the teleseismic, high-rate Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data, which provides an opportunity to understand the rupture characteristics of the Mexican subduction zone. Here, an integrated inversion strategy involving centroid moment tensor inversion and kinematic finite-fault inversion is used to study the rupture history of the 2020 Oaxaca earthquake. The fault geometry and source duration time derived from the centroid moment tensor solution are used as prior information in linear kinematic finite-fault joint inversion. The rupture initial point and relative weight of each dataset are determined to estimate a well-constrained rupture model. The finite-fault model shows the rupture expanded bilaterally around the hypocenter, the peak slip is 3.5 m, the main slip was located at a depth of 15–30 km, the whole rupture lasted about 20 s, and a 95% moment rate was released at 15 s. The half-duration of the finite-fault inversion is consistent with the centroid moment tensor inversion results (half-duration 9 s), which shows the good resolution of the temporal information. The total scalar moment was 1.5 × 1020 Nm, equivalent to a moment magnitude of Mw 7.4. The integrated inversion strategy used in this study is useful since the prior information can be derived and used to constrain the rupture process. Both the centroid moment tensor and finite-fault inversion mainly rely on identical temporal information provided by teleseismic P waveforms. The 2020 Oaxaca earthquake was mainly the interaction between Cocos and the North American plate, and the slow slip events may be the key factor affecting the seismogenic zone width in the Oaxaca region.https://www.frontiersin.org/articles/10.3389/feart.2022.951033/fullmoment tensorfinite-fault modeljoint inversionprior informationintegrated inversion strategy
spellingShingle Guisen Wen
Xingxing Li
Yingwen Zhao
Caijun Xu
Guangyu Xu
Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR Data
Frontiers in Earth Science
moment tensor
finite-fault model
joint inversion
prior information
integrated inversion strategy
title Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR Data
title_full Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR Data
title_fullStr Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR Data
title_full_unstemmed Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR Data
title_short Rupture Characteristics Analysis of the 2020 Mw 7.4 Oaxaca, Mexico Earthquake Using Teleseismic, High-Rate GPS, and InSAR Data
title_sort rupture characteristics analysis of the 2020 mw 7 4 oaxaca mexico earthquake using teleseismic high rate gps and insar data
topic moment tensor
finite-fault model
joint inversion
prior information
integrated inversion strategy
url https://www.frontiersin.org/articles/10.3389/feart.2022.951033/full
work_keys_str_mv AT guisenwen rupturecharacteristicsanalysisofthe2020mw74oaxacamexicoearthquakeusingteleseismichighrategpsandinsardata
AT xingxingli rupturecharacteristicsanalysisofthe2020mw74oaxacamexicoearthquakeusingteleseismichighrategpsandinsardata
AT yingwenzhao rupturecharacteristicsanalysisofthe2020mw74oaxacamexicoearthquakeusingteleseismichighrategpsandinsardata
AT caijunxu rupturecharacteristicsanalysisofthe2020mw74oaxacamexicoearthquakeusingteleseismichighrategpsandinsardata
AT guangyuxu rupturecharacteristicsanalysisofthe2020mw74oaxacamexicoearthquakeusingteleseismichighrategpsandinsardata