Interaction between seabed morphology and water masses around the seamounts on the Motril Marginal Plateau (Alboran Sea, Western Mediterranean)

Abstract

We analyzed in detail the seabed morphology of the seamounts and surroundings on the Djibouti Marginal Shelf (northern Alboran Sea) using high resolution (Sparker) and very high resolution (TOPAS) seismic reflection profiles and multibeam bathymetry. The aim of the study was to determine the recent geological processes, and in particular the contouritic processes associated with Mediterranean waters. Six groups of morphologic features were defined: structural features (seamount cap, tectonic depressions), fluid dynamics-related features (pockmarks), mass-movement features (gullies, slides), bottom-current features (moats, scour marks, terraces, elongated and separated drifts, plastered drifts, confined drifts, sheeted drifts), mixed features (ridges) and bioconstructions (carbonate mounds). The main processes controlling feature formation are Late Cenozoic tectonic activity and the interaction of Mediterranean waters with the seafloor topography. Seamounts act as topographic barriers that affect the pathway and velocity of Mediterranean water flows, which are subdivided into strands that interact with the surrounding seafloor. Sedimentary instability and fluiddynamic processes play a minor role, and their occurrence is probably triggered by seismicity.

Mollusca from a species-rich deep-water <em>Leptometra</em> community in the Alboran Sea

“…It covers an area of 83 km 2 and is surrounded by steep slopes reaching down to the plateau at nearly 800 m depth (Palomino et al 2011); it is therefore here considered a "bank" rather than a "seamount", following IHO guidelines which define a "seamount" as elevated more than 1000 m above the seafloor (IHO 2013). The summit of Algarrobo Bank is characterized by the occurrence of several mounds and ridges, and is covered by muddy-sandy sediments containing a large fraction of planktonic foraminiferal tests (Gil et al 2009, García-Muñoz et al 2012.…”

“…The Alboran Sea contains a wide variety of ecologically interesting seafloor structures, such as submarine canyons of varying size (Baro et al 2012), carbonate mounds (Lo Iacono et al 2008, Pardo et al 2011, submarine structures caused by fluid emissions such as pockmarks and mud volcanoes (Somoza et al 2012, Gennari et al 2013, and seamounts and banks of different heights and geologic origins (Palomino et al 2011). The diverse seafloor morphology and the location and peculiar hydrodynamic features of the Alboran Sea, with the mixing of Atlantic and Mediterranean waters, promote a wide diversity of habitats and associated biota that have been little studied in specific bathyal areas, especially at a microfaunal level (Salas 1996).…”

Multidisciplinary oil spill modeling to protect coastal communities and the environment of the Eastern Mediterranean Sea

“…The results of previous studies17181926 strongly support that seabed morphology is able to alter the hydrodynamic regime changing the water circulation pathways and affecting the sedimentary processes. Slopes in the Eastern Mediterranean Sea are generally steep, exceeding 40°, but with gentle continental shelves, seamount tops and abyssal areas on which slope gradients vary between 0° and 20° (Fig.…”

Mediterranean cold‐water corals – an important regional carbonate factory?

“…However, most CWC reports from the Mediterranean refer to sub‐fossil specimens (Delibrias & Taviani, ; McCulloch et al ., ). Living CWCs have been predominantly reported from submarine cliffs (Freiwald et al ., ), seamounts (Palomino et al ., ), flanks of submarine canyons (Orejas et al ., ; Fabri et al ., ), on pre‐existing highs (Taviani et al ., ; Malinverno et al ., ; Vertino et al ., ; Fink et al ., ), coral mounds and elongated coral ridges (Fink et al ., , ). They thrive in the present‐day Mediterranean Sea close to their ecological limit with respect to temperature and oxygen (Freiwald et al ., ).…”

“…To the east it opens to the south Balearic Basin. Living and fossil CWC occurrences are known from its northern (Lo Iacono et al ., , ; Coiras et al ., ), western (associated with mud volcanos; Margreth et al ., ), and southern margins (Fink et al ., ; Lo Iacono et al ., ) and from several seamounts (Palomino et al ., ; De Mol et al ., ). In 2006, several conical mounds and elongated ridge structures were discovered in 200 to 400 m water depth east of Trape Tres Forcas on the Moroccan margin of the Alboran Sea – the eastern Melilla coral province (Comas & Pinheiro, ).…”