True grit spells double trouble
Article Abstract:
The lead isotope analysis of feldspar grains from glacial and H-2 Heinrich event sediments shows that the source of sand in the Heinrich layers of the northeastern Atlantic is in the Churchill Province. The sediments surrounding the H-2 grains have been derived from the Churchill and Grenville Provinces, and the Appalachian range. Some sand may also have come from Scandinavia and Greenland. The study, based on the strontium content and isotopic composition of bulk samples from the last six Heinrich events and glacial sediments, shows that the sand is derived from Canada, Scandinavia and Britain.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1996
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Flickers within cycles
Article Abstract:
Global climate underwent frequent changes in the past 40,000 years, as shown by core drillings of Greenland ice. K.C. Taylor and colleagues studied dust concentrations in the samples and found that climate fluctuated in cycles as short as or even less than ten years. This research could lead to greater understanding of the greenhouse effect and help resolve the issue of whether the modern world has started on a global warming.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
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Sudden end of an interglacial
Article Abstract:
A detailed picture of ocean conditions during the previous interglacial has been presented, based on a new geochemical approach to sediment dating, by Adkins and colleagues. They build on work about abrupt temperature changes during glacial times, which may be caused by major changes in ocean circulation. The new results are taken from a sediment core from the Bermuda Rise in the western North Atlantic.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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