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K-Ar age of the late Pleistocene eruption of Toba, north Sumatra

D. Ninkovich·N. J. Shackleton·A. A. Abdel-Monem·J. D. Obradovich·G. Izett
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Abstract

The late Pleistocene eruption of Toba is the largest magnitude explosive eruption documented from the Quaternary. K-Ar dating of the uppermost unit of the Toba Tuff gives an age of [~amp]sim; 75,000 yr. A chemically and petrographically equivalent ash layer in deep-sea cores helps calibrate the Stage 4-5 boundary of the standard oxygen isotope stratigraphy. A similar ash in Malaya that overlies finds of Tampan Palaeolithic tools indicates that they are older than 75,000 yr. ?? 1978 Nature Publishing Group.

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D. Ninkovich, N. J. Shackleton, A. A. Abdel-Monem, J. D. Obradovich, G. Izett. 1978. K-Ar age of the late Pleistocene eruption of Toba, north Sumatra. https://doi.org/10.1038/276574a0

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