Nd, Pb and Sr isotopes in sediment cores from the Gulf of Cadiz and the Portuguese margin

• Main Authors: Stumpf, Roland, Frank, Martin, Schönfeld, Joachim, Haley, Brian A
• Format: Dataset
• Language: English
• Published: PANGAEA 2010
• Subjects: BC; Box corer; GC; GC10; GC22; GC45; Gravity corer; Gravity corer (Kiel type); Gulf of Cádiz; Atlantic Ocean; LV044-316; M39/1; M39/1_08-3; M39/1_36-4; M39/1_58-2; M39008-3; M39058-2; Maria S. Merian; Meteor (1986); MSM01/3; MSM01/3_139; MSM01/3_161; MSM01/3_168; MSM01/3_183; MSM01/3_190-2; MSM01/3_237-1; MSM01/3_240; MSM01/3_331; MUC; MUC11; MUC2; MUC4; MUC6; MUC9; MultiCorer; PALEO 1; Portuguese Margin; POS287; POS287_08-1B; POS287_14-1B; POS287_26-1B; Poseidon; SL; North Atlantic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.774216; https://doi.org/10.1594/PANGAEA.774216

Mediterranean Outflow Water (MOW) is characterised by higher temperatures and salinities than other ambient water masses. MOW spreads at water depths between 500 and 1500 m in the eastern North Atlantic and has been a source of salinity for the Atlantic Meridional Overturning Circulation in the North Atlantic. We used high-resolution Nd and Pb isotope records of past ambient seawater obtained from authigenic ferromanganese coatings of sediments in three gravity cores at 577, 1745 and 1974 m water depth in the Gulf of Cadiz and along the Portuguese margin complemented by a selection of surface sediments to reconstruct the extent and pathways of MOWover the past 23 000 years. The surface and downcore Nd isotope data from all water depths exhibit only a very small variability close to the present day composition of MOW but do not reflect the present day Nd isotopic stratification of the water column as determined from a nearby open ocean hydrographic station. In contrast, the Pb isotope records show significant and systematic variations, which provide evidence for a significantly different pattern of the MOW pathways between 20 000 and 12 000 years ago compared with the subsequent period of time.