Following iceberg footprints
Article Abstract:
Sedimentary layers on the Atlantic sea bed discovered recently to be rich in glacial deposits have been found to mark the paths of icebergs originating from North American ice sheets in the last ice age as much as 40,000 years ago. The sources of the layers are dolomite and limestone rocks in northern Canada, and the banded layers show the dispersal of the icebergs between Newfoundland and Europe from 40 to 50 degrees north latitude. Each deposit reveals the prevailing ocean currents and reflects a surge in the ice sheet. However, the fundamental causes of such surges are still open questions.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
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Rapid changes in the mechanism of ocean convection during the last glacial period
Article Abstract:
Research into two high-resolution mid-depth sediment cores from the Nordic Seas indicates that brine formation appears to be directly connected with a cessation or strong fall in open ocean convection, connected with periods of excess freshwater delivery to the surface ocean, and to Northern Hemisphere cold intervals. It is possible that shelf areas were potential source areas for intensive sea-ice formation. The creation of a net salinity flux to the north by brine formation could be a significant mechanism, permitting rapid changes to warm conditions, and thus the end of cold intervals.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
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Evidence for massive discharges of icebergs into the North Atlantic ocean during the last glacial period
Article Abstract:
Sedimentary deposits in the North Atlantic from the most recent ice age contain mineral detritus deposited by icebergs which can be traced to their origin 3,000 kilometers away in eastern Canada. The advance of the icebergs reflects a surface cooling which is difficult to explain. It may be explained by rapid advances in the Laurentide ice sheet, but ice core evidence from Greenland does not corroborate a contemporary decrease in air temperature. Furthermore, the iceberg discharges do not follow Milankovitch orbital periods.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
User Contributions:
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