Contourites and associated sediments controlled by deep-water circulation processes; state-of-the-art and future considerations

Online Access: Get full text
doi: 10.1016/j.margeo.2014.03.011
Author(s): Rebesco, Michele; Hernández-Molina, F. Javier; van Rooij, David; Wahlin, Anna
Author Affiliation(s): Primary:
Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, Sgonico, Italy
Royal Holloway-University of London, United Kingdom
Ghent University, Belgium
University of Goteborg, Sweden
Volume Title: 50th anniversary special issue; State of the art in marine geology
Volume Author(s): de Lange, Gert J., prefacer; Piper, David J. W.; Wells, John T.
Source: 50th anniversary special issue; State of the art in marine geology, prefaced by Gert J. de Lange, David J. W. Piper and John T. Wells. Marine Geology, Vol.352, p.111-154. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0025-3227 CODEN: MAGEA6
Note: In English. Includes appendices. 519 refs.; illus., incl. block diag., sects., 1 table, geol. sketch map
Summary: The contourite paradigm was conceived a few decades ago, yet there remains a need to establish a sound connection between contourite deposits, basin evolution and oceanographic processes. Significant recent advances have been enabled by various factors, including the establishment of two IGCP projects and the realisation of several IODP expeditions. Contourites were first described in the Northern and Southern Atlantic Ocean, and since then, have been discovered in every major ocean basin and even in lakes. The 120 major contourite areas presently known are associated to myriad oceanographic processes in surface, intermediate and deep-water masses. The increasing recognition of these deposits is influencing palaeoclimatology & palaeoceanography, slope-stability/geological hazard assessment, and hydrocarbon exploration. Nevertheless, there is a pressing need for a better understanding of the sedimentological and oceanographic processes governing contourites, which involve dense bottom currents, tides, eddies, deep-sea storms, internal waves and tsunamis. Furthermore, in light of the latest knowledge on oceanographic processes and other governing factors (e.g. sediment supply and sea-level), existing facies models must now be revised. Persistent oceanographic processes significantly affect the seafloor, resulting in large-scale depositional and erosional features. Various classifications have been proposed to subdivide a continuous spectrum of partly overlapping features. Although much progress has been made in the large-scale, geophysically based recognition of these deposits, there remains a lack of unambiguous and commonly accepted diagnostic criteria for deciphering the small-scaled contourite facies and for distinguishing them from turbidite ones. Similarly, the study of sandy deposits generated or affected by bottom currents, which is still in its infancy, offers great research potential: these deposits might prove invaluable as future reservoir targets. Expectations for the forthcoming analysis of data from the IODP Expedition 339 are high, as this work promises to tackle much of the aforementioned lack of knowledge. In the near future, geologists, oceanographers and benthic biologists will have to work in concert to achieve synergy in contourite research to demonstrate the importance of bottom currents in continental margin sedimentation and evolution. Abstract Copyright (2014) Elsevier, B.V.
Year of Publication: 2014
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 06 Petrology, Sedimentary; Atlantic Ocean; Bedforms; Bottom currents; Case studies; Clastic rocks; Clastic sediments; Contourite; Currents; Deep-sea environment; Density currents; Deposition; Eddies; Erosion; Erosion features; Expedition 339; Global; Gulf of Cadiz; Integrated Ocean Drilling Program; Internal waves; Lithofacies; Marine environment; Marine sediments; North Atlantic; Ocean circulation; Ocean currents; Paleo-oceanography; Paleoclimatology; Sedimentary rocks; Sedimentary structures; Sediments; Tidal currents
Coordinates: N361605 N373418 W0064700 W0100735
Record ID: 2014062341
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands