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Impact ejecta layer from the mid-Devonian: possible connection to global mass extinctions.

Brooks B Ellwood·Stephen L Benoist·Ahmed El Hassani·Christopher Wheeler·Rex E Crick
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Abstract

We have found evidence for a bolide impacting Earth in the mid-Devonian ( approximately 380 million years ago), including high concentrations of shocked quartz, Ni, Cr, As, V, and Co anomalies; a large negative carbon isotope shift (-9 per mil); and microspherules and microcrysts at Jebel Mech Irdane in the Anti Atlas desert near Rissani, Morocco. This impact is important because it is coincident with a major global extinction event (Kacák/otomari event), suggesting a possible cause-and-effect relation between the impact and the extinction. The result may represent the extinction of as many as 40% of all living marine animal genera.

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AnimalsClimateEcosystemGeologic SedimentsMagneticsMeteoroidsMoroccoSeawaterTimeJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Brooks B Ellwood, Stephen L Benoist, Ahmed El Hassani, Christopher Wheeler, Rex E Crick. 2003-06-13. Impact ejecta layer from the mid-Devonian: possible connection to global mass extinctions.. https://doi.org/10.1126/science.1081544

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