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Science 25 September 1987:
Vol. 237. no. 4822, pp. 1603 - 1605
DOI: 10.1126/science.237.4822.1603
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Articles

Fission-Track Dating of Haughton Astrobleme and Included Biota, Devon Island, Canada

GOMAA OMAR 1, KIRK R. JOHNSON 2, LEO J. HICKEY 2, P. BLYTH ROBERTSON 3, MARY R. DAWSON 4, and CATHY W. BARNOSKY 4

1 Department of Geology, University of Pennsylvania, Philadelphia, PA 19104.
2 Department of Geology and Geophysics, Yale University, New Haven, CT 06511.
3 Geological Survey of Canada, Ottawa, Ontario, Canada K1A 0Y3.
4 Carnegie Museum of Natural History, Pittsburgh, PA 15213.

Haughton Astrobleme is a major extraterrestrial impact structure located on Devon Island in the Canadian Arctic Archipelago, Northwest Territories. Apatite grains separated from shocked Precambrian gneiss contained in a polymict breccia from the center of the astrobleme yielded a fission-track date of 22.4 million ± 1.4 million years before the present or early Miocene (Aquitanian). This provides a date for the impact event and an upper limit on the age of crater-filling lake sediments and a flora and vertebrate fauna occurring in them. A geologically precise date for these fossils provides an important biostratigraphic reference point for interpreting the biotic evolution of the Arctic.

Submitted on April 20, 1987
Accepted on July 27, 1987


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Fission Track Dating of Phosphate Minerals and the Thermochronology of Apatite.
A. J.W. Gleadow, D. X. Belton, B. P. Kohn, and R. W. Brown (2002)
Reviews in Mineralogy and Geochemistry 48, 579-630
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