Data/hora: 02/06/2024 00:31:26

Provedor de dados: | Institutional Archive of Ifreme (ArchiMer)
País: | France
Título: | Processus et enregistrements sédimentaires dans les canyons sous-marins Bourcart et de Capbreton durant le dernier cycle climatique.
Autores: | Gaudin, Mathieu.
Data: | 2006-12-21
Ano: | 2006
Palavras-chave: | Seal level variations; Last climatic cycle; Gravity currents; Dense water cascading; Coarse grained sedimentation; Gulf of Lion; Bay of Biscay; Submarine canyon; Variations du niveau marin; Dernier cycle climatique; Courants gravitaires; Plongées d'eau dense; Sédimentation sableuse; Golfe du Lion; Golfe de Gascogne; Canyon sous marin.
Resumo: | Submarine canyons cutting continental shelves and slopes are considered to be erosive features allowing continental derived sediment to reach the deep sea. In order to better understand their sedimentary dynamic and morphologic evolution through time, two submarine canyons, the Bourcart canyon in the Gulf of Lion and the Capbreton canyon in the Bay of Biscay have been studied. The Bourcart canyon, located at the shelf break at 110 m water depth, is disconnected from direct sediment supply during sea-level highstand and is considered as inactive. The Capbreton canyon's head is located 400 m off the coastline, and is disconnected from the Adour river since the 16th century. Bathymetric, core, radioisotopic and current data showed that these canyons are active during sea-level highstand despite the fact that they are not directly connected to any fluvial system. Regional climatic and hydrodynamic processes, like dense water cascading or storm events, govern sediment erosion and transport, and allow coarse-grained sedimentation within the canyon. Seismic and geotechnical data also permitted to characterise the architecture and nature of sediments deposited within the canyons. Bourcart and Capbreton canyons morphologic evolution during the last climatic cycle is linked to sea-level variations, episodes of connexion/disconnection with a fluvial system and occurrence of high frequency climatic events.
Tipo: | Text
Idioma: | Francês
Identificador: | http://archimer.ifremer.fr/doc/2006/these-2511.pdf
Editor: | Université de Bordeaux 1
Relação: | http://archimer.ifremer.fr/doc/00000/2511/
Formato: | application/pdf