Planktic foraminifers, ice-rafted debris and stable isotopes from three sediment cores along the East/South Greenland margin
Sediment core GS16-204-22CC-A (58° 02.83 N, 47° 02.36 W, water depth 3160 m) was retrieved at the Eirik drift with R/V G.O. Sars in 2016. The core was sampled every 2 cm between 200 and 530.5 cm with a sample width of 0.5 cm. Bulk sample weights were taken prior to and after freeze-drying. Subsequen...
| Main Authors: | , , , , |
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| Format: | Other/Unknown Material |
| Language: | English |
| Published: |
PANGAEA
2019
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| Subjects: | |
| Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.904065 https://doi.org/10.1594/PANGAEA.904065 |
| Summary: | Sediment core GS16-204-22CC-A (58° 02.83 N, 47° 02.36 W, water depth 3160 m) was retrieved at the Eirik drift with R/V G.O. Sars in 2016. The core was sampled every 2 cm between 200 and 530.5 cm with a sample width of 0.5 cm. Bulk sample weights were taken prior to and after freeze-drying. Subsequently, the bulk samples were wet sieving (63 µm-sieve) and the coarse fraction was dry sieved into size fractions 63-106 µm, 106-150 µm, 150-500 µm, 500-1000 µm and > 1mm. Size fraction 150-500 µm was split (max. 4x) for foraminifer and IRD counts and the number was added to numbers counted in size fractions 500-1000 µm and > 1mm (results in >150 µm/g dry sediment). In order to calculate the according fluxes we multiplied the respective concentrations with the bulk mass accumulation rate following Peck et al. (2007). Hereby, a sediment particle, carbonate and water density of 2.650, 2.730 and 1.025 g cm-3 were assumed, respectively. Additionally, the ratio between lithic grains and planktic foraminifers was calculated using the following equation: lithic grains/total entities. Size fraction 150-500 µm was also used for the planktic foraminifer assemblage counts (min. 300 specimens), stable isotope analyses (N. pachyderma, 212-250 μm) and radiocarbon dating (N. pachyderma, 150-500 µm). Altogether eleven samples were dated at Beta Analytic Inc., Miami, US and at W. M. Keck Carbon Cycle Accelerator Mass Spectrometry Facility of University of California, Irvine, US (KCCAMS/UCI). For the final age model of GS16-204-22CC-A, three different types of control points are combined: two calibrated AMS 14C ages, one tephra layer (North Atlantic Ash Zone II) and seven secondary control points. The secondary control points are based on the synchronization of the planktic d18O and d13C time series of core GS16-204-22CC-A and core PS2644-5 from the Greenland Sea (Voelker & Haflidason, 2015) using the program AnalySeries (Paillard et al., 1996). Consequently, sedimentation rates vary between ~2.5 and 12 cm/ky. Paillard, D., ... |
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