Stable isotope ratios on planktonic foraminifer N. pachyderma of surface sediments from the Arctic Ocean (Table 1)

• Main Authors: Spielhagen, Robert F, Erlenkeuser, Helmut
• Format: Dataset
• Language: English
• Published: PANGAEA 1994
• Subjects: 125SGC; 83-101; 83-104; 83-106; 83-109; 83-110; 83-201; 83-202; 83-203; 83-204; 83-205; Alpha Ridge; Arctic Ocean; Amerasian Basin; Amundsen Basin; Antarctic Ocean; ARK-III/3; ARK-IV/3; ARK-IX/4; ARK-VIII/2; ARK-VIII/3; Barents Sea; CESAR; CESAR_83-101; CESAR_83-104; CESAR_83-106; CESAR_83-109; CESAR_83-110; CESAR_83-201; CESAR_83-202; CESAR_83-203; CESAR_83-204; CESAR_83-205; D.St.A.2; DEPTH; sediment/rock; Elevation of event; Event label; FL-433; FL-523; Fram-I; FramI/4; FramI/7; FramII/1; FramII/3; FramII/4; FramII/5; FramIII/1; FramIII/2; Arctic; Antarctic; North Pole; Gakkel Ridge; alpha ridge; amundsen basin; Antarc*; Fram Strait; Nansen Basin; Neogloboquadrina pachyderma; Sea ice
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.53230; https://doi.org/10.1594/PANGAEA.53230

Planktic foraminifers Neogloboquadrina pachyderma (sin.) from 87 eastern and central Arctic Ocean surface sediment samples were analyzed for stable oxygen and carbon isotope composition. Additional results from 52 stations were taken from the literature. The lateral distribution of delta18O (18O/16O) values in the Arctic Ocean reveals a pattern of roughly parallel, W-E stretching zones in the Eurasian Basin, each ~0.5 per mil wide on the delta18O scale. The low horizontal and vertical temperature variability in the Arctic halocline waters (0-100 m) suggests only little influence of temperature on the oxygen isotope distribution of N. pachyderma (sin.). The zone of maximum delta18O values of up to 3.8 per mil is situated in the southern Nansen Basin and relates to the tongue of saline (> 33%.) Atlantic waters entering the Arctic Ocean through the Fram Strait. delta18O values decrease both to the Barents Shelf and to the North Pole, in accordance with the decreasing salinities of the halocline waters. In the Nansen Basin, a strong N-S delta18O gradient is in contrast with a relatively low salinity change and suggests contributions from different freshwater sources, i.e. salinity reduction from sea ice meltwater in the south and from light isotope waters (meteoric precipitation and river-runoff) in the northern part of the basin. North of the Gakkel Ridge, delta18O and salinity gradients are in good accordance and suggest less influence of sea ice melting processes. The delta13C (13C/12C) values of N. pachyderma (sin.) from Arctic Ocean surface sediment samples are generally high (0.75-0.95 per mil). Lower values in the southern Eurasian Basin appear to be related to the intrusion of Atlantic waters. The high delta13C values are evidence for well ventilated surface waters. Because the perennial Arctic sea ice cover largely prevents atmosphere-ocean gas exchange, ventilation on the seasonally open shelves must be of major importance. Lack of delta13C gradients along the main routes of the ice drift from the ...