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Evidence for a Solar Flare Cause of the Pleistocene Mass Extinction

Published online by Cambridge University Press:  18 July 2016

Paul A LaViolette
Paul A LaViolette*
Affiliation:
The Starburst Foundation, 1176 Hedgewood Lane, Niskayuna, New York 12309, USA. Email: [email protected].
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Abstract

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The hypothesis is presented that an abrupt rise in atmospheric radiocarbon concentration evident in the Cariaco Basin varve record at 12,837 ± 10 cal yr BP, contemporaneous with the Rancholabrean termination, may have been produced by a super-sized solar proton event (SPE) having a fluence of ~1.3 × 1011 protons/cm2. A SPE of this magnitude would have been large enough to deliver a lethal radiation dose of at least 3–6 Sv to the Earth's surface, and hence could have been a principal cause of the final termination of the Pleistocene megafauna and several genera of smaller mammals and birds. The event time-correlates with a large-magnitude acidity spike found at 1708.65 m in the GISP2 Greenland ice record, which is associated with high NO-3 ion concentrations and a rapid rise in 10Be deposition rate, all of which are indicators of a sudden cosmicray influx. The depletion of nitrate ions within this acidic ice layer suggests that the snowpack surface at that time was exposed to intense UV for a prolonged period, which is consistent with a temporary destruction of the polar ozone layer by solar cosmic rays. The acidity event also coincides with a large-magnitude, abrupt climatic excursion and is associated with elevated ammonium ion concentrations, an indicator of global fires.

Type
Methods and Developments
Information
Radiocarbon , Volume 53 , Issue 2 , 2011 , pp. 303 - 323
Copyright
Copyright © The American Journal of Science 

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