En conclusion, on constate que les canyons de la marge occidentale algérienne présentent des
changements dans leur configuration géométrique, d'Est en Ouest et du haut vers le bas du talus
continental, ce qui lui confère un contraste morphologique. Différents paramètres agissent
probablement simultanément dans le temps et l'espace pour contrôler la localisation des canyons,
leur initiation et leur évolution sur la marge, notamment les variations du niveau de la mer,
l'apport sédimentaire, la morphologie de la marge, l'histoire géodynamique de la marge et la
tectonique compressive.
Mots clés :
Marge ouest algérienne, Canyons sous-marins, Analyse morphométrique, Erosion régressive,
Tectonique compressive.
Abstract:
Continental margins, whether passive or active, are the main pathway for sediment
transfer between the continental shelf and the abyssal plains. The continental slopes are the site
of erosion/deposition processes controlled by the transfer of continental particle flows channelled
through erosive structures, such as submarine canyons, and then redistributed to the entire
margin. Canyons strongly erode continental slopes and contribute to the evolution of their
morphology over time. However, there are submarine canyons that are not related to the presence
of a river system. As a result, the formation and evolution of submarine canyons are still poorly
understood.
The Algerian margin is a passive margin located in the south of the western Mediterranean that
developed as a back-arc basin behind the subduction of the Tethyan Ocean underneath the
African plate during the Miocene. Presently in compression, it is one of the most seismically
active areas in the Western Mediterranean, having experienced several moderate to strong
earthquakes in the coastal zone during the last century. The morphology of the continental slope
offshore Algeria is steep and dominated by the presence of numerous canyons of variable size
and sea-floor escarpments that are probably the expression of active thrust-folds. As a result, the
morphology of the canyon reflects the interplay between tectonic deformation and canyon
evolution.
changements dans leur configuration géométrique, d'Est en Ouest et du haut vers le bas du talus
continental, ce qui lui confère un contraste morphologique. Différents paramètres agissent
probablement simultanément dans le temps et l'espace pour contrôler la localisation des canyons,
leur initiation et leur évolution sur la marge, notamment les variations du niveau de la mer,
l'apport sédimentaire, la morphologie de la marge, l'histoire géodynamique de la marge et la
tectonique compressive.
Mots clés :
Marge ouest algérienne, Canyons sous-marins, Analyse morphométrique, Erosion régressive,
Tectonique compressive.
Abstract:
Continental margins, whether passive or active, are the main pathway for sediment
transfer between the continental shelf and the abyssal plains. The continental slopes are the site
of erosion/deposition processes controlled by the transfer of continental particle flows channelled
through erosive structures, such as submarine canyons, and then redistributed to the entire
margin. Canyons strongly erode continental slopes and contribute to the evolution of their
morphology over time. However, there are submarine canyons that are not related to the presence
of a river system. As a result, the formation and evolution of submarine canyons are still poorly
understood.
The Algerian margin is a passive margin located in the south of the western Mediterranean that
developed as a back-arc basin behind the subduction of the Tethyan Ocean underneath the
African plate during the Miocene. Presently in compression, it is one of the most seismically
active areas in the Western Mediterranean, having experienced several moderate to strong
earthquakes in the coastal zone during the last century. The morphology of the continental slope
offshore Algeria is steep and dominated by the presence of numerous canyons of variable size
and sea-floor escarpments that are probably the expression of active thrust-folds. As a result, the
morphology of the canyon reflects the interplay between tectonic deformation and canyon
evolution.