Article first published online: 3 JUN 2011
©1996. American Geophysical Union. All Rights Reserved.
Eos, Transactions American Geophysical Union
Volume 77, Issue 40, page 386, 1 October 1996
How to Cite
1996), Elemental evidence, Eos Trans. AGU, 77(40), 386–386, doi:10.1029/EO077i040p00386-02.(
- Issue published online: 3 JUN 2011
- Article first published online: 3 JUN 2011
- Cited By
He set out to prove that ocean sediments contain elevated levels of the rare element iridium because of the natural weathering of the continents. Instead, what Ariel Anbar found was new evidence that a meteorite may have had a role in the mass extinctions that marked the end of the Cretaceous era.
By studying the geochemical properties of iridium, Anbar, a professor of earth and environmental sciences and chemistry at the University of Rochester, found that the residence time—a measure of the rate at which an element settles out of water into sediments—of iridium in ocean water is 2000 to 20,000 years. That finding suggests that a large deposit of iridium could have lingered in the world's oceans long enough to explain the thickness of the iridium-rich sediment layers at the K-T boundary.