(Table 1) Age control points and dating methods for sediment cores of the Sea of Okhotsk

Marine- and terrestrial-derived biomarkers (alkenones, brassicasterol, dinosterol, and long-chain n-alkanes), as well as carbonate, biogenic opal, and ice-rafted debris (IRD), were measured in two sediment cores in the Sea of Okhotsk, which is located in the northwestern Pacific rim and characterize...

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Bibliographic Details
Main Authors: Seki, Osamu, Ikehara, M, Kawamura, Kimitaka, Nakatsuda, T, Ohnishi, K, Wakatsuchi, M, Narita, H, Sakamoto, Tatsuhiko
Format: Dataset
Language:English
Published: PANGAEA 2015
Subjects:
Age
comment
Age model
DEPTH
sediment/rock
Elevation of event
Event label
Latitude of event
Longitude of event
PC
PC-2
PC-4
Piston corer
Sea of Okhotsk
Sedimentation rate
XP98-PC-1
XP98-PC-2
XP98-PC-4
Okhotsk
Pacific
Sea ice
Online Access:https://doi.pangaea.de/10.1594/PANGAEA.841213
https://doi.org/10.1594/PANGAEA.841213
Description
Summary:Marine- and terrestrial-derived biomarkers (alkenones, brassicasterol, dinosterol, and long-chain n-alkanes), as well as carbonate, biogenic opal, and ice-rafted debris (IRD), were measured in two sediment cores in the Sea of Okhotsk, which is located in the northwestern Pacific rim and characterized by high primary productivity. Down-core profiles of phytoplankton markers suggest that primary productivity abruptly increased during the global Meltwater Pulse events 1A (about 14 ka) and 1B (about 11 ka) and stayed high in the Holocene. Spatial and temporal distributions of the phytoplankton productivity were found to be consistent with changes in the reconstructed sea ice distribution on the basis of the IRD. This demonstrates that the progress and retreat of sea ice regulated primary productivity in the Sea of Okhotsk with minimum productivity during the glacial period. The mass accumulation rates of alkenones, CaCO3, and biogenic opal indicate that the dominant phytoplankton species during deglaciation was the coccolithophorid, Emiliania huxleyi, which was replaced by diatoms in the late Holocene. Such a phytoplankton succession was probably caused by an increase in silicate supply to the euphotic layer, possibly associated with a change in surface hydrography and/or linked to enhanced upwelling of North Pacific Deep Water.

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