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Updated: Jul 22, 2026
08:16
Ice Generation and the Heat and Mass Transfer Phenomena of Introducing Water to a Cold Bath of Brine
Published on: March 13, 2017
The first glacial maximum in North America.
Greg Balco1, Charles W Rovey, John O H Stone
1Quaternary Research Center and Department of Earth and Space Sciences, University of Washington, Seattle, WA 98915, USA. balcs@u.washington.edu
Science (New York, N.Y.)
|January 18, 2005
Summary
Scientists can now date ancient glacial deposits using cosmic ray-produced nuclides. This new method, using beryllium-10 and aluminum-26, allows for the reconstruction of older ice sheet advances from terrestrial evidence.
Area of Science:
- Geology
- Quaternary Science
- Geochronology
Background:
- Marine records indicate at least 50 Pliocene-Pleistocene ice sheet advances.
- Reconstructing older glacial deposits from terrestrial evidence is challenging due to limited dating techniques.
Purpose of the Study:
- To establish a reliable method for dating older glacial deposits using terrestrial evidence.
- To enable accurate reconstruction of past ice sheet dynamics.
Main Methods:
- Utilizing cosmic ray-produced nuclides: beryllium-10 (10Be) and aluminum-26 (26Al).
- Applying these nuclides to date tills overlying paleosols.
Main Results:
- Demonstrated the efficacy of 10Be and 26Al in dating tills.
- Successfully dated glacial deposits that were previously undatable.
Conclusions:
- Cosmic ray-nuclide dating provides a new tool for reconstructing Pliocene-Pleistocene ice sheet history.
- This method overcomes limitations of previous techniques for dating older glacial deposits.
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