Stable isotope ratios measured on carbonate tests from the Kara Sea, supplement to: Simstich, Johannes; Erlenkeuser, Helmut; Spielhagen, Robert F; Stanovoy, Vladimir V (2005): Modern and Holocene hydrographic characteristics of the shallow Kara Sea shelf (Siberia) as reflected by stable isotopes of bivalves and benthic foraminifera. Boreas, 34(3), 252-263


River discharge of Ob and Yenisei to the Kara Sea is highly variable on seasonal and interannual time scales. River water dominates the shallow bottom water near the river mouths, making it warmer and less saline but seasonally and interannually more changeable than bottom water on the deeper shelf. This hydrographic pattern shows up in measurements and modelling, and in stable isotope records (delta18O, delta13C) along the growth axis of bivalve shells and in multiple analyses of single benthic foraminiferal shells. Average isotope ratios increase, but sample-internal variability decreases with water depth and distance from river mouths. However, isotope records of bivalves and foraminifera of a sediment core from a former submarine channel of Yenisei River reveal a different pattern. The retreat of the river mouth from this site due to early Holocene sea level rise led to increasing average isotope values up core, but not to the expected decrease of the in-sample isotope variability. Southward advection of cold saline water along the palaeo-river channel probably obscured the hydrographic variability during the early Holocene. Later, when sediment filled the channel, the hydrographic variability at the core location remained low, because the shallowing proceeded synchronously with the retreat of the river mouth.

Related Identifier
Metadata Access
Creator Spielhagen, Robert F; Simstich, Johannes; Erlenkeuser, Helmut; Stanovoy, Vladimir V
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2005
Rights Creative Commons Attribution 3.0 Unported
OpenAccess true
Language English
Resource Type Supplementary Collection of Datasets
Format application/zip
Size 13 datasets
Discipline Earth System Research
Spatial Coverage (72.662W, 72.050S, 89.333E, 77.927N); Kara Sea
Temporal Coverage Begin 1997-09-15T18:01:00Z
Temporal Coverage End 2001-09-10T00:00:00Z