FN Archimer Export Format PT J TI Mayotte seismic crisis: building knowledge in near real-time by combining land and ocean-bottom seismometers, first results BT AF Saurel, Jean-Marie Jacques, Eric Aiken, Chastity Lemoine, Anne Retailleau, Lise Lavayssière, Aude Foix, Oceane Dofal, Anthony Laurent, Angèle Mercury, Nicolas Crawford, Wayne Lemarchand, Arnaud Daniel, Romuald Pelleau, Pascal de Berc, Maxime Bès Dectot, Grégoire Bertil, Didier Roullé, Agathe Broucke, Céleste Colombain, Alison Jund, Hélène Besançon, Simon Guyavarch, Pierre Kowalski, Philippe Roudaut, Mickael Apprioual, Ronan Battaglia, Jean Bodihar, Soumya Boissier, Patrice Bouin, Marie Paule Brunet, Christophe Canjamale, Kévin Catherine, Philippe Desfete, Nicolas Doubre, Cécile Dretzen, Rémi Dumouche, Tom Fernagu, Philippe Ferrazzini, Valérie Fontaine, Fabrice Gaillot, Arnaud Géli, Louis Griot, Cyprien Grunberg, Marc Guzel, Emre Can Hoste-Colomer, Roser Lambotte, Sophie Lauret, Frédéric Léger, Félix Maros, Emmanuel Peltier, Aline Vergne, Jérôme Satriano, Claudio Tronel, Frédéric Van der Woerd, Jérôme Fouquet, Yves Jorry, Stephan Rinnert, Emmanuel Thinon, Isabelle Feuillet, Nathalie AS 1:1;2:1;3:2;4:3;5:1,4;6:1;7:2;8:1,5;9:1;10:3,6;11:1;12:1;13:1;14:2;15:6;16:7;17:3;18:3;19:8;20:3;21:8;22:1;23:2;24:1,4;25:2;26:2;27:9;28:1;29:1,4;30:1;31:1,4;32:1,4;33:1,4;34:1,4;35:6;36:8;37:1;38:2;39:1,4;40:1,5;41:2;42:2;43:1,4;44:8;45:10;46:3;47:6;48:1,4;49:1;50:2;51:1,4;52:8;53:1;54:7;55:6;56:2;57:2;58:2;59:11;60:1; FF 1:;2:;3:PDG-REM-GM-LAD;4:;5:;6:;7:PDG-REM-GM-LAD;8:;9:;10:;11:;12:;13:;14:PDG-REM-GM-CTDI;15:;16:;17:;18:;19:;20:;21:;22:;23:PDG-REM-GM-CTDI;24:;25:PDG-REM-GM-CTDI;26:PDG-REM-GM-CTDI;27:;28:;29:;30:;31:;32:;33:;34:;35:;36:;37:;38:PDG-REM-GM-LCG;39:;40:;41:PDG-REM-GM-CTDI;42:PDG-REM-GM-LAD;43:;44:;45:;46:;47:;48:;49:;50:PDG-REM-GM-CTDI;51:;52:;53:;54:;55:;56:PDG-REM-GM-LCG;57:PDG-REM-GM-LGS;58:PDG-REM-GM-LCG;59:;60:; C1 Université de Paris, Institut de Physique du Globe de Paris, CNRS, F-75005 Paris, France IFREMER, Centre de Bretagne, –Unité Géosciences Marines, 1625 Rte de Ste Anne, 29280 Plouzané, France BRGM, French Geological Survey, Risk and Prevention Division, F- 45100 Orléans, France Observatoire volcanologique du Piton de la Fournaise, Institut de Physique du Globe de Paris, F-97418 La Plaine des Cafres, La Réunion, France Université de La Réunion, Laboratoire GéoSciences Réunion, F-97744 Saint Denis, La Réunion, France ITES, Institut Terre Environnement de Strasbourg, UMR 7063, CNRS Université de Strasbourg, 5, rue René Descartes, 67084 Strasbourg BRGM, French Geological Survey, Regional Division (Mayotte), F-97600 Mamoudzou, Mayotte, France EOST, Université de Strasbourg/CNRS, 5 rue Descartes, 67084 Strasbourg Cedex, France Université Clermont Auvergne, CNRS, IRD, OPGC, Laboratoire Magmas et Volcans, F-63000 Clermont-Ferrand, France Istanbul Technical University, turkey BRGM, French Geological Survey, Georesources, F-45100 Orléans, France C2 UNIV PARIS, FRANCE IFREMER, FRANCE BRGM, FRANCE IPGP, FRANCE UNIV LA REUNION, FRANCE UNIV STRASBOURG, FRANCE BRGM, FRANCE UNIV STRASBOURG, FRANCE UNIV CLERMONT AUVERGNE, FRANCE UNIV TECH ISTANBUL, TURKEY BRGM, FRANCE SI BREST SE PDG-REM-GM-LAD PDG-REM-GM-CTDI PDG-REM-GM-LCG PDG-REM-GM-LGS UM GEO-OCEAN IN WOS Ifremer UMR copubli-france copubli-p187 copubli-univ-france copubli-int-hors-europe copubli-sud IF 2.8 TC 5 UR https://archimer.ifremer.fr/doc/00724/83604/88621.pdf https://archimer.ifremer.fr/doc/00724/83604/88622.pdf LA English DT Article CR MAYOBS MAYOBS1 BO Marion Dufresne DE ;Indian Ocean;Volcano seismology;Volcano monitoring;Africa;Remote sensing of volcanoes AB The brutal onset of seismicity offshore Mayotte island North of the Mozambique Channel, Indian Ocean, that occurred in May 2018 caught the population, authorities, and scientific community off guard. Around 20 potentially felt earthquakes were recorded in the first 5 days, up to magnitude Mw 5.9. The scientific community had little pre-existing knowledge of the seismic activity in the region due to poor seismic network coverage. During 2018 and 2019, the MAYOBS/REVOSIMA seismology group was progressively built between four French research institutions to improve instrumentation and data sets to monitor what we know now as an on-going exceptional sub-marine basaltic eruption. After the addition of 3 medium-band stations on Mayotte island and 1 on Grande Glorieuse island in early 2019, the data recovered from the Ocean Bottom Seismometers were regularly processed by the group to improve the location of the earthquakes detected daily by the land network. We first built a new local 1D velocity model and established specific data processing procedures. The local 1.66 low VP/VS ratio we estimated is compatible with a volcanic island context. We manually picked about 125,000 P and S phases on land and sea bottom stations to locate more than 5,000 events between February 2019 and May 2020. The earthquakes outline two separate seismic clusters offshore that we named Proximal and Distal. The Proximal cluster, located 10km offshore Mayotte eastern coastlines, is 20 to 50 km deep and has a cylindrical shape. The Distal cluster start 5 km to the east of the Proximal cluster and extends below Mayotte's new volcanic edifice, from 50 km up to 25 km depth. The two clusters appear seismically separated, however our dataset is insufficient to firmly demonstrate this. PY 2022 PD FEB SO Geophysical Journal International SN 0956-540X PU Oxford University Press (OUP) VL 228 IS 2 UT 000741352300020 BP 1281 EP 1293 DI 10.1093/gji/ggab392 ID 83604 ER EF