Oxygen Isotopes in Biogenic Silica: Global Changes in Ocean Temperature and Isotopic Composition

A record of oxygen isotopes in biogenic silica from a deep-sea sediment core from the Southern Ocean reveals that marine diatoms retain their primary isotopic composition after burial. As a result, the marine diatom record can be combined with data on coexisting planktonic foraminifera to monitor pa...

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Bibliographic Details
Published in:Science
Main Authors: Shemesh, A., Charles, C. D., Fairbanks, R. G.
Format: Article in Journal/Newspaper
Language:English
Published: American Association for the Advancement of Science (AAAS) 1992
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Online Access:http://dx.doi.org/10.1126/science.256.5062.1434
https://www.science.org/doi/pdf/10.1126/science.256.5062.1434
Description
Summary:A record of oxygen isotopes in biogenic silica from a deep-sea sediment core from the Southern Ocean reveals that marine diatoms retain their primary isotopic composition after burial. As a result, the marine diatom record can be combined with data on coexisting planktonic foraminifera to monitor past surface temperature and isotopic composition of seawater. The coupling of these two records allows the solution of two paleotemperature equations for each core interval. Data from a South Atlantic core show that the average δ 18 O during the glacial period at this site was higher by about 1.3 per mil than average Holocene values, and that average glacial-age temperatures were not significantly different from average Holocene values.