Mass flux, major components and the Lead 210 concentration of sediment collected using a Bottom Boundary (BOBO) lander at the Gardar Drift in the North Atlantic

• Main Author: Jonkers, Lukas
• Format: Dataset
• Language: English
• Published: PANGAEA 2022
• Subjects: Alpha spectrometry; Benthic bottom boundary lander; BOBO lander; Calcium carbonate; Calculated; Carbon; organic; total; Carlo Erba Flash 1112 elemental analyser; contourite; Date/time end; Date/time start; Gardar_Drift; Lead-210; standard deviation; Lithogenic material; Mass flux; Nitrogen; Opal; biogenic silica; Sample code/label; sediment trap; Sequential leaching technique; Split; Technicap PPS4/3; Total mass; flux per day; North Atlantic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.947855; https://doi.org/10.1594/PANGAEA.947855

To monitor particle fluxes and near bottom hydrographic variability a modified version of the benthic Bottom Boundary (BOBO) lander was deployed at 57 29.09 N, 27 54.53 W on the Gardar Drift at a water depth of 2630 m. The lander was fitted with three extended Technicap PPS 4/3 sediment traps, each with a baffled collecting area of 0.05 m2 positioned at 4 metres above the seafloor. Trap bottles were filled with ambient seawater and poisoned with a pH-buffered HgCl2 solution and rotated every 11 days. To test the performance of each sediment trap, two traps were programmed to collect material synchronously for three intervals during the deployment. Fluxes were intercepted successfully from 2007-09-19 through 2008-08-03. Full details about the deployment can be found in Jonkers et al., 2010 (doi:10.1016/j.dsr.2010.05.005). Pitch and roll of the lander were recorded and displayed very little variation (1.8370.031 and 0.3370.041, respectively); trapping efficiency was thus uncompromised by the movement of the lander. Upon recovery the pH of the supernatant was measured and found to range from 8.5 to 8.8, indicating minimum sample degradation. The samples were stored at 4 degC. Before sample processing in the laboratory the supernatant was sampled for dissolved Si analysis to correct for the dissolution of the particulate biogenic silica (doi:10.1016/j.margeo.2005.11.001; doi:10.1016/S0967-0645(97)00018-0). Swimmers larger than 1 mm were removed prior to splitting of the samples for further analysis. Carbon and nitrogen were separately analysed on weighed aliquots of the bulk material before and after removal of the carbonate-carbon (doi:10.1016/S0967-0637(02)00030-4) using a Carlo Erba Instruments Flash 1112 elemental analyzer. Biogenic silica (BSi) was determined by continuous alkaline leaching that accounts for contributions by co-leaching of Al-silicates (doi:10.1023/A:1020318610178). The lithogenic content was calculated according to doi:10.1016/S0924-7963(02)00189-6. Samples were analysed for 210Pb activity ...