| Summary: | IV Congress of Marine Sciences, 11-13 June 2014, Las Palmas de Gran Canaria.-- 2 pages A high-resolution multiproxy study of core KTA-GC-05 (46.18595 N, 18.31385 W; 3939 m below sea level; 337 cm long) has been carried out in order to investigate the effects of millennial and submillennial climatic changes on the Northeast Atlantic oceanography during the last climate cycle. This approach includes physical properties (Multi-sensor Core Logger, MSCL, and Computerized Tomography, CT), lithological, sedimentological and geochemical characterization, and oxygen and carbon stable isotope analyses in monospecific samples of planktonic foraminifera G. bulloides. Integrated information from independent proxies that show common trends along the core enables distinguishing three units. The basal unit (at around 120 cm thick) is mainly composed by nannoplankton and foraminifera oozes with three intercalated intervals characterized by higher amounts of coarse and very coarse terrigenous silt. Oxygen stable isotopes (18O) values and micropaleontological features, as well as other proxies suggest this basal unit was deposited during the Last Interglacial (Marine Isotope Stage 5, MIS 5). Many other proxies, as terrigenous markers (Fe/Ti, K/Ti) but also biogenic input (Ca/Ti, TIC) and grain-size parameters fluctuate according the same pattern. Higher values of these markers and lighter 18O could correspond with warmer substages of MIS 5. These data from warmer subestages suggest higher contribution of terrigenous particles due to enhanced Atlantic Meridional Overturning Circulation (AMOC), although the pelagic contribution was dominant. On the contrary, intervals characterized by low values of terrigenous proxies and finer grain sizes in the non-carbonate fractions could corresponds with relatively colder substages and weaker bottom currents. The second unit (at around 190 cm thick) presents darker colors and a broader variety of facies. CaCO3 content is lower than that of previous unit and conversely the terrigenous ...
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