Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards Istanbul
Abstract Analysis of earthquake rupture directivity provides key information for seismic hazard and risk assessment, particularly for faults near urban areas. We analyze directivity patterns for 31 well‐constrained ML≥ 3.5 earthquakes along the Main Marmara Fault, in direct proximity to Istanbul. We...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2025-01-01
|
| Series: | Geophysical Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1029/2024GL111460 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832593490136006656 |
|---|---|
| author | Xiang Chen Patricia Martínez‐Garzón Grzegorz Kwiatek Yehuda Ben‐Zion Marco Bohnhoff Fabrice Cotton |
| author_facet | Xiang Chen Patricia Martínez‐Garzón Grzegorz Kwiatek Yehuda Ben‐Zion Marco Bohnhoff Fabrice Cotton |
| author_sort | Xiang Chen |
| collection | DOAJ |
| description | Abstract Analysis of earthquake rupture directivity provides key information for seismic hazard and risk assessment, particularly for faults near urban areas. We analyze directivity patterns for 31 well‐constrained ML≥ 3.5 earthquakes along the Main Marmara Fault, in direct proximity to Istanbul. We calculate source mechanisms with a waveform modeling approach and analyze earthquake directivity from apparent source‐time functions using empirical Green's functions. Most of the strike‐slip earthquakes to the west of the Princes Islands segment display a predominantly asymmetric rupture toward the east with the median directivity trending 85°, consistent with the Main Marmara Fault strike. Consequently, earthquake ground shaking may be more pronounced toward Istanbul. This holds potentially for a large earthquake on the Main Marmara Fault which is late in its seismic cycle. Our results motivate the importance of evaluating the impact of eastward asymmetric ruptures on the probabilistic seismic hazard and risk assessment around Istanbul. |
| format | Article |
| id | doaj-art-a38fe50b439241fab65ed49c2d77015d |
| institution | Kabale University |
| issn | 0094-8276 1944-8007 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geophysical Research Letters |
| spelling | doaj-art-a38fe50b439241fab65ed49c2d77015d2025-01-20T13:05:57ZengWileyGeophysical Research Letters0094-82761944-80072025-01-01521n/an/a10.1029/2024GL111460Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards IstanbulXiang Chen0Patricia Martínez‐Garzón1Grzegorz Kwiatek2Yehuda Ben‐Zion3Marco Bohnhoff4Fabrice Cotton5Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam GermanyHelmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam GermanyHelmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam GermanyDepartment of Earth Sciences University of Southern California Los Angeles CA USAHelmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam GermanyHelmholtz Centre Potsdam GFZ German Research Centre for Geosciences Potsdam GermanyAbstract Analysis of earthquake rupture directivity provides key information for seismic hazard and risk assessment, particularly for faults near urban areas. We analyze directivity patterns for 31 well‐constrained ML≥ 3.5 earthquakes along the Main Marmara Fault, in direct proximity to Istanbul. We calculate source mechanisms with a waveform modeling approach and analyze earthquake directivity from apparent source‐time functions using empirical Green's functions. Most of the strike‐slip earthquakes to the west of the Princes Islands segment display a predominantly asymmetric rupture toward the east with the median directivity trending 85°, consistent with the Main Marmara Fault strike. Consequently, earthquake ground shaking may be more pronounced toward Istanbul. This holds potentially for a large earthquake on the Main Marmara Fault which is late in its seismic cycle. Our results motivate the importance of evaluating the impact of eastward asymmetric ruptures on the probabilistic seismic hazard and risk assessment around Istanbul.https://doi.org/10.1029/2024GL111460rupture directivitysource parameterssource mechanismsground motionearthquake physicsseismic hazard |
| spellingShingle | Xiang Chen Patricia Martínez‐Garzón Grzegorz Kwiatek Yehuda Ben‐Zion Marco Bohnhoff Fabrice Cotton Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards Istanbul Geophysical Research Letters rupture directivity source parameters source mechanisms ground motion earthquake physics seismic hazard |
| title | Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards Istanbul |
| title_full | Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards Istanbul |
| title_fullStr | Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards Istanbul |
| title_full_unstemmed | Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards Istanbul |
| title_short | Rupture Directivity of Moderate Earthquakes Along the Main Marmara Fault Suggests Larger Ground Motion Towards Istanbul |
| title_sort | rupture directivity of moderate earthquakes along the main marmara fault suggests larger ground motion towards istanbul |
| topic | rupture directivity source parameters source mechanisms ground motion earthquake physics seismic hazard |
| url | https://doi.org/10.1029/2024GL111460 |
| work_keys_str_mv | AT xiangchen rupturedirectivityofmoderateearthquakesalongthemainmarmarafaultsuggestslargergroundmotiontowardsistanbul AT patriciamartinezgarzon rupturedirectivityofmoderateearthquakesalongthemainmarmarafaultsuggestslargergroundmotiontowardsistanbul AT grzegorzkwiatek rupturedirectivityofmoderateearthquakesalongthemainmarmarafaultsuggestslargergroundmotiontowardsistanbul AT yehudabenzion rupturedirectivityofmoderateearthquakesalongthemainmarmarafaultsuggestslargergroundmotiontowardsistanbul AT marcobohnhoff rupturedirectivityofmoderateearthquakesalongthemainmarmarafaultsuggestslargergroundmotiontowardsistanbul AT fabricecotton rupturedirectivityofmoderateearthquakesalongthemainmarmarafaultsuggestslargergroundmotiontowardsistanbul |