A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu Case
Abstract The 2018 Mw7.5 Palu earthquake is a remarkable strike‐slip event due to its nature as a shallow supershear fault rupture across several segments and a destructive tsunami that followed coseismic deformation. GPS offsets in the wake of the 2018 earthquake display a transient in the surface m...
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| Format: | Article |
| Language: | English |
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Wiley
2021-04-01
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| Series: | Geochemistry, Geophysics, Geosystems |
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| Online Access: | https://doi.org/10.1029/2020GC009491 |
| _version_ | 1827771730554257408 |
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| author | N. Nijholt W. J. F. Simons J. Efendi D. A. Sarsito R. E. M. Riva |
| author_facet | N. Nijholt W. J. F. Simons J. Efendi D. A. Sarsito R. E. M. Riva |
| author_sort | N. Nijholt |
| collection | DOAJ |
| description | Abstract The 2018 Mw7.5 Palu earthquake is a remarkable strike‐slip event due to its nature as a shallow supershear fault rupture across several segments and a destructive tsunami that followed coseismic deformation. GPS offsets in the wake of the 2018 earthquake display a transient in the surface motions of northwest Sulawesi. A Bayesian approach identifies (predominantly aseismic) deep afterslip on and below the coseismic rupture plane as the dominant physical mechanism causing the cumulative, postseismic, surface displacements whereas viscous relaxation of the lower crust and poro‐elastic rebound contribute negligibly. We confirm a correlation between shallow supershear rupture and postseismic surface transients with afterslip activity in the zone below an interseismically locked fault plane where the slip rate tapers from zero to creeping. |
| first_indexed | 2024-03-11T12:58:22Z |
| format | Article |
| id | doaj.art-4acf30b6a3204ecf8c881ea78a517c89 |
| institution | Directory Open Access Journal |
| issn | 1525-2027 |
| language | English |
| last_indexed | 2024-03-11T12:58:22Z |
| publishDate | 2021-04-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geochemistry, Geophysics, Geosystems |
| spelling | doaj.art-4acf30b6a3204ecf8c881ea78a517c892023-11-03T16:55:42ZengWileyGeochemistry, Geophysics, Geosystems1525-20272021-04-01224n/an/a10.1029/2020GC009491A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu CaseN. Nijholt0W. J. F. Simons1J. Efendi2D. A. Sarsito3R. E. M. Riva4Department of Geoscience and Remote Sensing Faculty of Civil Engineering and Geosciences Delft University of Technology Delft The NetherlandsDepartment of Space Engineering Faculty of Aerospace Engineering Delft University of Technology Delft The NetherlandsBIG (Badan Informasi Geospasial/Geospatial Information Agency) Java IndonesiaFaculty of Earth Sciences and Technology ITB (Institut Teknologi Bandung/Institute of Technology Bandung) Geodesy Research Group Bandung IndonesiaDepartment of Geoscience and Remote Sensing Faculty of Civil Engineering and Geosciences Delft University of Technology Delft The NetherlandsAbstract The 2018 Mw7.5 Palu earthquake is a remarkable strike‐slip event due to its nature as a shallow supershear fault rupture across several segments and a destructive tsunami that followed coseismic deformation. GPS offsets in the wake of the 2018 earthquake display a transient in the surface motions of northwest Sulawesi. A Bayesian approach identifies (predominantly aseismic) deep afterslip on and below the coseismic rupture plane as the dominant physical mechanism causing the cumulative, postseismic, surface displacements whereas viscous relaxation of the lower crust and poro‐elastic rebound contribute negligibly. We confirm a correlation between shallow supershear rupture and postseismic surface transients with afterslip activity in the zone below an interseismically locked fault plane where the slip rate tapers from zero to creeping.https://doi.org/10.1029/2020GC009491afterslipBayesian inferenceGPSpostseismic deformationstrike‐slip faultSulawesi |
| spellingShingle | N. Nijholt W. J. F. Simons J. Efendi D. A. Sarsito R. E. M. Riva A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu Case Geochemistry, Geophysics, Geosystems afterslip Bayesian inference GPS postseismic deformation strike‐slip fault Sulawesi |
| title | A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu Case |
| title_full | A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu Case |
| title_fullStr | A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu Case |
| title_full_unstemmed | A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu Case |
| title_short | A Transient in Surface Motions Dominated by Deep Afterslip Subsequent to a Shallow Supershear Earthquake: The 2018 Mw7.5 Palu Case |
| title_sort | transient in surface motions dominated by deep afterslip subsequent to a shallow supershear earthquake the 2018 mw7 5 palu case |
| topic | afterslip Bayesian inference GPS postseismic deformation strike‐slip fault Sulawesi |
| url | https://doi.org/10.1029/2020GC009491 |
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