Turbidity currents transport clastic sediments from the continental margin to deep ocean basins and along their pathways they erode large submarine channels. The driving mechanisms for submarine channel evolution are highly complex, reflected by recent debates about the formation and global distribution of sinuosity in turbidite channels. We present novel experiments on channelized gravity currents running over an erodible bed, where the magnitude of Coriolis forces is changed to reproduce conditions at low and high latitudes. We find a striking systematic change in deposition and erosion patterns as Coriolis forces become dominant at high latitudes so that erosion and deposition occur only on opposite sides of channels; in contrast, at low latitudes significant inner-bank intra-channel bars form on alternate sides of sinuous channels. Our observations show very good agreement with sedimentation patterns in Coriolis-dominated contourite drift systems and with deposits in modern and ancient turbidity current channels. We hypothesize that Coriolis forces are a key parameter for submarine channel evolution and sedimentary architecture at high latitudes but not at low latitudes; this proposal offers a new approach to interpret deep-sea architectural features at high latitudes.

Item Type:	Refereed Article
Keywords:	density and turbidity currents, submarine channels
Research Division:	Earth Sciences
Research Group:	Oceanography
Research Field:	Physical Oceanography
Objective Division:	Transport
Objective Group:	Water Transport
Objective Field:	Water Transport not elsewhere classified
Author:	Cossu, R (Dr Remo Cossu)
ID Code:	98257
Year Published:	2015
Web of Science® Times Cited:	9
Deposited By:	NC Maritime Engineering and Hydrodynamics
Deposited On:	2015-02-09
Last Modified:	2016-06-21
Downloads:	0