Inicio  /  Geosciences  /  Vol: 9 Par: 8 (2019)  /  Artículo
ARTÍCULO
TITULO

133,000 Years of Sedimentary Record in a Contourite Drift in the Western Alboran Sea: Sediment Sources and Paleocurrent Reconstruction

Nieves López-González    
Belén Alonso    
Carmen Juan    
Gemma Ercilla    
Graziella Bozzano    
Isabel Cacho    
David Casas    
Desirée Palomino    
Juan-Tomás Vázquez    
Ferran Estrada    
Patricia Bárcenas    
Elia d?Acremont    
Christian Gorini and Bouchta El Moumni    

Resumen

The Djibouti Ville Drift is part of a contourite depositional system located on the southern side of the Djibouti Ville Seamount in the Alboran Sea (Western Mediterranean). The sedimentary record of a core located in the drift deposits has been characterized to achieve the possible sediment sources for the Saharan dust supply and the paleocurrent variability related to Mediterranean intermediate waters for the last 133 kyr. Three end-member grain-size distributions characterize the sediment record transported by the bottom current to address the different aeolian populations, i.e., coarse EM1, silty EM2, and fine EM3. For these particles, the most likely source areas are the Saharan sedimentary basins and deserts, as well as the cratonic basins of the Sahara-Sahel Dust Corridor. The prevalence of these main source areas is shown in the core record, where a noticeable change occurs during the MIS 5 to MIS 4 transition. Some punctual sediment inputs from the seamount have been recognized during sea-level lowstand, but there is no evidence of fluvial supply in the drift deposits. The paleocurrent reconstruction allows the characterizing of the stadial and cold periods by large increases in the mean sortable silt fraction and UP10, which point to an enhanced bottom current strength related to intermediate water masses. Conversely, interglacial periods are characterized by weaker bottom current activity, which is associated with denser deep water masses. These proxies also recorded the intensified Saharan wind transport that occurred during interstadial/stadial transitions. All these results point to the importance of combining sediment source areas with major climatic oscillations and paleocurrent variability in palaeoceanographic sedimentary archives, which may help to develop future climate prediction models.

 Artículos similares

       
 
Valle Raidla, Joonas Pärn, Werner Aeschbach, György Czuppon, Jüri Ivask, Madis Kiisk, Robert Mokrik, Vytautas Samalavicius, Siiri Suursoo, Siim Tarros and Therese Weissbach    
The Viimsi peninsula is located north-east of Tallinn, capital of Estonia. The Cambrian-Vendian (Cm-V) aquifer system is a sole source of drinking water in the area. Historically, the groundwater exploitation has led to freshening of groundwater in the p... ver más
Revista: Geosciences

 
Sarah Parcak, Gregory Mumford and Chase Childs    
This paper will assess the most recently available open access high-resolution optical satellite data (0.3 m?0.6 m) and its detection of buried ancient features versus ground based remote sensing tools. It also discusses the importance of CORONA satellit... ver más
Revista: Geosciences

 
Artur Ionescu, Pierfrancesco Burrato, Calin Baciu, Giuseppe Etiope and Boglarka-Mercedesz Kis    
Seeps are the expression of the migration of hydrocarbons from subsurface accumulations to the surface in sedimentary basins. They may represent an important indication of the presence of petroleum (gas and oil) reservoirs and faults, and are a natural s... ver más
Revista: Geosciences