Fission-Track Dating of Haughton Astrobleme and Included Biota, Devon Island, Canada
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...
Published in: | Science |
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Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Association for the Advancement of Science (AAAS)
1987
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Subjects: | |
Online Access: | http://dx.doi.org/10.1126/science.237.4822.1603 https://www.science.org/doi/pdf/10.1126/science.237.4822.1603 |
Summary: | 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. |
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