The Agadir Slide offshore NW Africa: Morphology, emplacement dynamics, and potential contribution to the Moroccan Turbidite System

Li, Wei, Krastel, Sebastian, Alves, Tiago M, Urlaub, Morelia, Mehringer, Lisa, Schuerer, Anke, Feldens, Peter, Cross, Felix, Stevenson, Christopher J ORCID: 0000-0003-0406-9892 and Wynn, Russell B (2018) The Agadir Slide offshore NW Africa: Morphology, emplacement dynamics, and potential contribution to the Moroccan Turbidite System. EARTH AND PLANETARY SCIENCE LETTERS, 498. pp. 436-449.

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Abstract

A newly identified large-scale submarine landslide on the NW African margin (Agadir Slide) is investigated in terms of its morphology, internal architecture, timing, and emplacement processes using high-resolution multibeam bathymetry data, 2D seismic profiles, and gravity cores. The Agadir Slide is located south of the Agadir Canyon at a water depth ranging from 500 m to 3,500 m, showing an estimated affected area of approximately 5,500 km2. The analysis of the Agadir Slide's complex morphology reveals the presence of two headwall areas and two slide fairways (the Western and Central slide fairways). Volume calculations indicate that ∼340 km3 of sediment were accumulated downslope along the slide fairways (∼270 km3) and inside the Agadir Canyon (∼70 km3). Stratigraphic correlations based on five gravity cores indicate an emplacement age of 142±1 ka for the Agadir Slide. However, its emplacement dynamics suggest that the slide was developed in two distinct, successive stages. The presence of two weak layers (glide planes) is a major preconditioning factor for the occurrence of slope instability in the study area, and local seismicity related to fault activity and halokinesis likely triggered the Agadir Slide. Importantly, the Agadir Slide neither disintegrated into sediment blocks nor was transformed into turbidity currents. The emplacement timing of the Agadir Slide does not correlate with any turbidites cored downslope across the Moroccan Turbidite System.

Item Type:	Article
Uncontrolled Keywords:	Agadir submarine slide, turbidity current, multibeam bathymetry, Moroccan Turbidite System, Northwest Africa
Depositing User:	Symplectic Admin
Date Deposited:	17 Jul 2018 15:47
Last Modified:	19 Jan 2023 01:30
DOI:	10.1016/j.epsl.2018.07.005
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3023862