Please use this identifier to cite or link to this item:
Authors: Khripounoff, A.* 
Crassous, P.* 
Lo Bue, N.* 
Dennielou, B.* 
Silva Jacinto, R.* 
Title: Different types of sediment gravity flows detected in the Var submarine canyon (northwestern Mediterranean Sea)
Issue Date: 19-Sep-2012
Series/Report no.: /106 (2013)
DOI: 10.1016/j.pocean.2012.09.001
Keywords: submarine canyon
gravity flows
Subject Classification03. Hydrosphere::03.02. Hydrology::03.02.02. Hydrological processes: interaction, transport, dynamics 
Abstract: Current velocities and vertical sediment fluxes in the Var submarine canyon were assessed at three stations respectively at 800 m, 1200 m and 1800 m depth, using moorings deployed for 4 months during winter 2008–2009. During this period, we observed three major sediment gravity flows, all characterized by sudden increases in current velocity that lasted 2–5 h and by downward particle fluxes. Each gravity flow, described using a high frequency current meter and two Acoustic Doppler Current Profiler (75 and 300 kHz ADCP) showed distinctive features. The first event, triggered during a flood of the Var River, was determined to be a hyperpycnal current with a large vertical extent (>100 m high) and relatively low velocity (40 cm s 1). The second event, observed after a Var River flood, was more energetic with a maximum horizontal current peak of 60 cm s 1 but with a low vertical extent (30 m high). This event was considered to be a turbidity landslide. The third was the result of a local canyon wall failure. It was characterized by a speed of >85 cm s 1. These peaks of current speed were associated with large clouds of material that transported sediment along the canyon and reached up to 200 g m 2 d 1 of sediment (>1 g m 2 d 1 of organic carbon). Our measurements in the Var canyon show the important role of gravity flows transporting particulate matter to the deep-sea floor. These large inputs of sediment and organic carbon may have a significant impact on deep-sea carbon storage in the Mediterranean Sea.
Appears in Collections:Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
AK-progress.pdfarticle2.79 MBAdobe PDFView/Open
Show full item record

Page view(s)

Last Week
Last month
checked on Aug 18, 2018


checked on Aug 18, 2018

Google ScholarTM