Skip to Main Content
Book Chapter

Glacial contourites on the Antarctic Peninsula margin: insight for palaeoenvironmental and palaeoclimatic conditions

By
Renata G. Lucchi
Renata G. Lucchi
Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Borgo Grotta Gigante 42/c, 34010 Sgonico (Trieste), ItalyPresent address: GRC Geociències Marines, Departament d'Estratigrafia, P. i Geociències Marines, Universitat de Barcelona, Facultat de Geologia, C/Martí i Franquès, s/n, E-08028 Barcelona, Spain (e-mail: rglucchi@ub.edu)
Search for other works by this author on:
Michele Rebesco
Michele Rebesco
Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Borgo Grotta Gigante 42/c, 34010 Sgonico (Trieste), Italy
Search for other works by this author on:
Published:
January 01, 2007

Abstract:

Deep-sea finely laminated and barren glacial sediments occur in the sediment drift field offshore the Pacific margin of the Antarctic Peninsula where a weak contour current flows at present to the SW. Atypical sedimentary facies were related to the coexistence and interaction of different sedimentary processes. Three 'end-members' of radiograph facies were defined to represent the sedimentary sequences controlled by a dominant process, as follows. (1) Direct influence of turbidity currents on sedimentation is observed in the area surrounding the Alexander Channel system with silty layers interbedded with laminated mud free of ice-rafted debris (IRD). (2) Distal meltwater turbid flows dominate the more proximal area of the top plateau with structureless and coarser-grained sediments containing IRD. (3) Along the crest of the drift, persistent weak bottom currents control the deposition of fine-grained sediments conveyed into the system through other processes. These laminated sediments contain IRD and are, atypically, not bioturbated, because of unusual, climatically related, environmental conditions of suppressed primary productivity and oxygen-reduced deep waters. These glacial contourites were observed on most of the Antarctic margin with the exception of the areas in which polynyas were maintained during the glacial stages. Glacial contourites can be used as a proxy to define temporal and spatial extension of the Antarctic sea-ice.

You do not currently have access to this article.

Figures & Tables

Contents

Geological Society, London, Special Publications

Economic and Palaeoceanographic Significance of Contourite Deposits

A. R. Viana
A. R. Viana
Petrobras, Brazil
Search for other works by this author on:
M. Rebesco
M. Rebesco
Petrobras, Brazil
Search for other works by this author on:
Geological Society of London
Volume
276
ISBN electronic:
9781862395244
Publication date:
January 01, 2007

GeoRef

References

Related

Citing Books via

A comprehensive resource of eBooks for researchers in the Earth Sciences

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal