Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of Aden
Earthquake swarms occur sporadically at divergent plate boundaries but their recurrence over multiple decades and relation to magmatic spreading activity remain poorly understood. Here we study more than 100 earthquake swarms over a 60-year period in the southern Red Sea, Afar, and Gulf of Aden regi...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2021-08-01
|
| Series: | Frontiers in Earth Science |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/articles/10.3389/feart.2021.664673/full |
| _version_ | 1819094583552770048 |
|---|---|
| author | Joël Ruch Joël Ruch Derek Keir Luigi Passarelli Luigi Passarelli Domenico Di Giacomo Ghebrebrhan Ogubazghi Sigurjón Jónsson |
| author_facet | Joël Ruch Joël Ruch Derek Keir Luigi Passarelli Luigi Passarelli Domenico Di Giacomo Ghebrebrhan Ogubazghi Sigurjón Jónsson |
| author_sort | Joël Ruch |
| collection | DOAJ |
| description | Earthquake swarms occur sporadically at divergent plate boundaries but their recurrence over multiple decades and relation to magmatic spreading activity remain poorly understood. Here we study more than 100 earthquake swarms over a 60-year period in the southern Red Sea, Afar, and Gulf of Aden region. We first compiled an earthquake-swarm catalogue by integrating reexamined global and local earthquake catalogues from 1960 to 2017. This yielded 134 earthquake swarms that mainly cluster in 19 different areas in the study region, showing that in most cases swarms recur every few decades in the same area. The swarms exhibit a range of earthquake magnitudes and often include multiple M3 to M5 events with some swarms having occasional larger earthquakes over M6, primarily in southern Afar. Many of the earthquake swarms were clearly associated with rifting events, consisting of magmatic intrusions, surface faulting, and in some cases volcanic eruptions. Together, the swarms suggest that extension at these divergent plate boundaries occurs episodically along <100 km long segments, some of which were previously unrecognized. Within the study region, the Gulf of Aden shows the most frequent swarm activity, followed by Afar and then the southern Red Sea. The results show that the three areas were subject to an increase of earthquake-swarm activity from 2003 to 2013 in the form of three rifting episodes and at least seven volcanic eruptions. We interpret that the most likely controls on temporal variations in earthquake swarm activity are either temporal variations in magma supply, or rifting-induced stress change that trigger clusters of swarms. |
| first_indexed | 2024-12-21T23:29:43Z |
| format | Article |
| id | doaj.art-54862bd19ce3456d8e36c9cc3ed78541 |
| institution | Directory Open Access Journal |
| issn | 2296-6463 |
| language | English |
| last_indexed | 2024-12-21T23:29:43Z |
| publishDate | 2021-08-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Earth Science |
| spelling | doaj.art-54862bd19ce3456d8e36c9cc3ed785412022-12-21T18:46:31ZengFrontiers Media S.A.Frontiers in Earth Science2296-64632021-08-01910.3389/feart.2021.664673664673Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of AdenJoël Ruch0Joël Ruch1Derek Keir2Luigi Passarelli3Luigi Passarelli4Domenico Di Giacomo5Ghebrebrhan Ogubazghi6Sigurjón Jónsson7Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi ArabiaDepartment of Earth Sciences, University of Geneva, Geneva, SwitzerlandSchool of Ocean and Earth Science, University of Southampton, Southampton, United KingdomPhysical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi ArabiaDepartment of Earth Sciences, University of Geneva, Geneva, SwitzerlandInternational Seismological Centre, Thatcham, United KingdomDepartment of Earth Sciences, Eritrea Institute of Technology, Asmara, EritreaPhysical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi ArabiaEarthquake swarms occur sporadically at divergent plate boundaries but their recurrence over multiple decades and relation to magmatic spreading activity remain poorly understood. Here we study more than 100 earthquake swarms over a 60-year period in the southern Red Sea, Afar, and Gulf of Aden region. We first compiled an earthquake-swarm catalogue by integrating reexamined global and local earthquake catalogues from 1960 to 2017. This yielded 134 earthquake swarms that mainly cluster in 19 different areas in the study region, showing that in most cases swarms recur every few decades in the same area. The swarms exhibit a range of earthquake magnitudes and often include multiple M3 to M5 events with some swarms having occasional larger earthquakes over M6, primarily in southern Afar. Many of the earthquake swarms were clearly associated with rifting events, consisting of magmatic intrusions, surface faulting, and in some cases volcanic eruptions. Together, the swarms suggest that extension at these divergent plate boundaries occurs episodically along <100 km long segments, some of which were previously unrecognized. Within the study region, the Gulf of Aden shows the most frequent swarm activity, followed by Afar and then the southern Red Sea. The results show that the three areas were subject to an increase of earthquake-swarm activity from 2003 to 2013 in the form of three rifting episodes and at least seven volcanic eruptions. We interpret that the most likely controls on temporal variations in earthquake swarm activity are either temporal variations in magma supply, or rifting-induced stress change that trigger clusters of swarms.https://www.frontiersin.org/articles/10.3389/feart.2021.664673/fullearthquake swarmAfar depressionseismicity analysisRed Sea—Gulf of Adenrifting and breakupvolcanism |
| spellingShingle | Joël Ruch Joël Ruch Derek Keir Luigi Passarelli Luigi Passarelli Domenico Di Giacomo Ghebrebrhan Ogubazghi Sigurjón Jónsson Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of Aden Frontiers in Earth Science earthquake swarm Afar depression seismicity analysis Red Sea—Gulf of Aden rifting and breakup volcanism |
| title | Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of Aden |
| title_full | Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of Aden |
| title_fullStr | Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of Aden |
| title_full_unstemmed | Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of Aden |
| title_short | Revealing 60 years of Earthquake Swarms in the Southern Red Sea, Afar and the Gulf of Aden |
| title_sort | revealing 60 years of earthquake swarms in the southern red sea afar and the gulf of aden |
| topic | earthquake swarm Afar depression seismicity analysis Red Sea—Gulf of Aden rifting and breakup volcanism |
| url | https://www.frontiersin.org/articles/10.3389/feart.2021.664673/full |
| work_keys_str_mv | AT joelruch revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden AT joelruch revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden AT derekkeir revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden AT luigipassarelli revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden AT luigipassarelli revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden AT domenicodigiacomo revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden AT ghebrebrhanogubazghi revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden AT sigurjonjonsson revealing60yearsofearthquakeswarmsinthesouthernredseaafarandthegulfofaden |