Seafloor earthquake ruptures and mass wasting from the 2004 Mw 6.3 Les Saintes submarine earthquake

Type Article
Date 2023-07-22
Language English
Author(s) Hughes AlexORCID1, Escartín Javier2, Billant Jeremy3, Leclerc FrédériqueORCID3, Andreani MurielORCID4, Olive Jean-ArthurORCID2, Arnaubec AurelienORCID5, Dano Alexandre3, Delorme Arthur1, Deplus ChristineORCID1, Feuillet NathalieORCID1, Gini CarolineORCID6, Gracias Nuno7, Hamelin Cédric8, Istenič Klemen7, Komorowski Jean-ChristopheORCID1, Le Friant Anne1, Marchand Claire9, Mével Catherine1, Onstad Solveig Lie10, Quidelleur Xavier11
Affiliation(s) 1 : Université Paris Cité, Institut de Physique du Globe de Paris, CNRS, F-75005, Paris, France
2 : Laboratoire de Géologie, Ecole Normale Supérieure (CNRS UMR 8538), PSL Research University, Paris, France
3 : Université Côte d’Azur, CNRS, Observatoire de la Côte d’Azur, IRD, Valbonne, France
4 : Laboratoire de Géologie de Lyon, Université de Lyon, ENS de Lyon, CNRS, UMR 5276 LGL-TPE, 69622, Villeurbanne, France
5 : IFREMER, Ctr Mediterranee, Unité Syst. Marins, CS 20330, F-83507, La Seyne Sur Mer, France
6 : Department of Earth Sciences, Memorial University of Newfoundland, St John’s, NL, Canada
7 : Computer Vision and Robotics Institute, University of Girona, Girona, Spain
8 : Independent Scholar, Søndre Skogveien 7, 5055, Bergen, Norway
9 : Sea Operations Division, iXblue, 6 Quai François Mitterrand, NEF XX, 13600, La Ciotat, France
10 : University of Bergen Centre for Deep Sea Research, Bergen, Norway
11 : Université Paris-Saclay, CNRS, GEOPS, Orsay, 91405, France
Source Communications Earth & Environment (2662-4435) (Springer Science and Business Media LLC), 2023-07-22 , Vol. 4 , N. 1 , P. 270 (13p.)
DOI 10.1038/s43247-023-00919-x
Keyword(s) Geomorphology, Natural hazards, Tectonics
Abstract

The seismic hazard posed by submarine faults and the capacity of submarine earthquakes to trigger mass wasting are poorly understood because we lack detailed characterizations of coseismic ruptures at the seafloor. Here, we present comprehensive mapping of a seafloor rupture caused by the 2004 Mw 6.3 Les Saintes earthquake on the Roseau normal fault in the Lesser Antilles. We report the visual characteristics, displacement profile, and note pronounced asymmetry of the rupture that bears similarities with well-studied subaerial normal fault ruptures. We also identify footwall-derived mass wasted debris that locally cover the coseismic rupture, and show that ground accelerations of 0.1–0.2 g can trigger submarine mass wasting events in well consolidated bedrock along unstable, over-steepened, scarps. Our study demonstrates the potential of underwater vehicles for detailed mapping of seafloor ruptures and hints at a key role for earthquakes in shaping submarine bedrock landscapes by triggering mass wasting events.

Full Text
File Pages Size Access
Publisher's official version 13 7 MB Open access
Supplementary Information 4 424 KB Open access
Peer Review File 17 3 MB Open access
Description of Additional Supplementary File 1 84 KB Open access
Supplementary Data 70 KB Open access
Top of the page

How to cite 

Hughes Alex, Escartín Javier, Billant Jeremy, Leclerc Frédérique, Andreani Muriel, Olive Jean-Arthur, Arnaubec Aurelien, Dano Alexandre, Delorme Arthur, Deplus Christine, Feuillet Nathalie, Gini Caroline, Gracias Nuno, Hamelin Cédric, Istenič Klemen, Komorowski Jean-Christophe, Le Friant Anne, Marchand Claire, Mével Catherine, Onstad Solveig Lie, Quidelleur Xavier (2023). Seafloor earthquake ruptures and mass wasting from the 2004 Mw 6.3 Les Saintes submarine earthquake. Communications Earth & Environment, 4(1), 270 (13p.). Publisher's official version : https://doi.org/10.1038/s43247-023-00919-x , Open Access version : https://archimer.ifremer.fr/doc/00847/95905/