Linked turbidite–debrite resulting from recent Sahara Slide headwall reactivation


Georgiopoulou, Aggeliki, Wynn, Russell B., Masson, Douglas G. and Frenz, Michael (2009) Linked turbidite–debrite resulting from recent Sahara Slide headwall reactivation. Marine and Petroleum Geology, 26, (10), 2021-2031. (doi:10.1016/j.marpetgeo.2009.02.013).

Download

Full text not available from this repository.

Description/Abstract

The northwest African margin has been affected by numerous large-scale landslides during the late Quaternary. This study focuses on a recent collapse of the Sahara Slide headwall and characterises the resulting flow deposit. Core and seismic data from the base of the upper headwall reveal the presence of blocky slide debris, comprising heavily deformed hemipelagic slope sediments. The blocky slide debris spilled over a lower headwall 60 km downslope and formed a thick transparent debris flow unit. Cores recovered 200–250 km farther downslope contain a surficial turbidite that is interpreted to be linked to the headwall collapse event based on timing and composition. One core located approximately 200 km from the headwall scar (C13) contains debrite encased in turbidite. The debrite comprises sheared and contorted hemipelagic mudstone clasts similar as those seen in the vicinity of the Sahara Slide headwall, and lacks matrix. This debrite pinches out laterally within 25 km of C13, whereas the accompanying turbidite can be correlated across 700 km of the northwest African margin. The linked turbidite–debrite bed is interpreted to have formed through recent failure of the steep Sahara Slide headwall that either 1) generated both a debris flow and a turbidity current almost simultaneously, or 2) generated a debris flow which with entrainment of water and progressive dilution led to formation of an accompanying turbidity current.

Item Type: Article
ISSNs: 0264-8172 (print)
Related URLs:
Keywords: Sahara Slide; Turbidite; Linked debrite; Northwest Africa; Canary Islands
Subjects: Q Science > QE Geology
Divisions: University Structure - Pre August 2011 > School of Ocean & Earth Science (SOC/SOES)
University Structure - Pre August 2011 > National Oceanography Centre (NERC)
ePrint ID: 71625
Date Deposited: 15 Dec 2009
Last Modified: 27 Mar 2014 18:51
URI: http://eprints.soton.ac.uk/id/eprint/71625

Actions (login required)

View Item View Item