English
 
Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Quantification of gravitational mass wasting and controls on submarine scarp morphology along the Roseau fault, Lesser Antilles

Authors

Hughes ,  Alex
External Organizations;

Escartín ,  Javier
External Organizations;

Olive ,  Jean‐Arthur
External Organizations;

Billant ,  Jeremy
External Organizations;

Deplus ,  Christine
External Organizations;

Feuillet ,  Nathalie
External Organizations;

Leclerc ,  Frédérique
External Organizations;

/persons/resource/malatest

Malatesta,  Luca C.
4.7 Earth Surface Process Modelling, 4.0 Geosystems, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum;

External Ressource
No external resources are shared
Fulltext (public)

5006088.pdf
(Publisher version), 15MB

Supplementary Material (public)
There is no public supplementary material available
Citation

Hughes, A., Escartín, J., Olive, J., Billant, J., Deplus, C., Feuillet, N., Leclerc, F., Malatesta, L. C. (2021): Quantification of gravitational mass wasting and controls on submarine scarp morphology along the Roseau fault, Lesser Antilles. - Journal of Geophysical Research: Earth Surface, 126, 4, e2020JF005892.
https://doi.org/10.1029/2020JF005892


Cite as: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5006088
Abstract
Due to challenges involved in mapping the seafloor at high‐resolution (e.g., < 2 m), data are lacking to understand processes that control the evolution of submarine normal fault scarps, which cover large parts of the global seafloor. Here, we use data from autonomous deep‐sea vehicles to quantify local erosion and deposition associated with a pronounced tectonic surface scarp formed by slip on the submarine Roseau normal fault (Lesser Antilles). We use high‐resolution video imagery, photomosaics, and high‐resolution bathymetry data (0.1–10 m/pixel) to identify active erosional features on the scarp including channels, steep gullies, small scarps, and debris cones. We compare volumes of erosion and deposition and find that under certain depositional conditions, debris cones effectively record the erosion signal of mass wasting from the footwall with a ratio of hanging wall deposition to footwall erosion of 0.80. We use eroded volumes to estimate earthquake‐induced landslide erosion rates for the Roseau fault of 14–46 m Ma‐1. Assuming mass wasting of the Roseau fault scarp is mostly coseismic, the erosion rates for the Roseau fault imply that submarine earthquake induced mass‐wasting can occur at similar rates to various terrestrial lithological and tectonic settings. We present a process‐based model of submarine scarp degradation via retrogressive erosion in basement lithology where scarps have a gravitational stability threshold height of 20–40 m and a long‐term average slope of 30–40°. More generally, the results presented here may be applicable to develop models of submarine landscape evolution based on degradation of normal fault scarps on the seafloor.