Evolution of the Gulf of Cadiz Margin and southwest Portugal contourite depositional system based on IODP Expedition 339 resultstectonic, sedimentary and paleoceanographic implications
- F.Javier Hernández-Molina
- F.J. Sierro
- E. Llave
- C. Roque
- D.A.V. Stow
- T. Williams
- J. Lofi
- M. Van der Schee
- A. Arnaíz
- S. Ledesma
- C. Rosales
- F.J. Rodríguez-Tovar
- E. Pardo-Igúzquiza
- R.E. Brackenridge
ISSN: 1576-5172
Any de publicació: 2016
Títol de l'exemplar: IX CONGRESO GEOLÓGICO DE ESPAÑA
Número: 16
Pàgines: 597-600
Tipus: Article
Altres publicacions en: Geotemas (Madrid)
Resum
The contourite depositional systems (CDS) along the southwestern Iberian Margin (SIM), within the Gulf of Cadiz and offshore areas of western Portugal bear the unmistakable signal of Mediterranean Outflow Water (MOW) exiting the Strait of Gibraltar. The Integrated Ocean Drilling Program (IODP) Expedition 339 drilled in 2012 five sites in the Gulf of Cadiz and two sites on the western Iberian margin. The integration of IODP Exp. 339 data along with other geophysical and wells databases and onshore outcrops analysis leads us to propose a new stratigraphic framework for the latest Miocene, Pliocene and Quaternary and refine our understanding of the SIM’s sedimentary evolution. We identify significant changes in sedimentation style and dominant sedimentary processes, coupled with widespread depositional hiatuses along the SIM. Sedimentation is controlled by a combination of tectonics, sediment supply, sea-level, climate and bottom-currents. This research identifies time scales of tectonic controls on deep-marine sedimentation, specifically over periods of 2.5 - >0.4 Ma, and shorter-term climatic (orbital) mechanisms control at time scales of ≤0.4 Ma.