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Text Description: 25-cm-thick-tephra; consists of thin, bubble-wall shards. Orthopyroxene, plagioclase, magnetite, and ilmenite are relatively abundant in the small crystal component, which also contains minor amounts of clinopyroxene, apatite, and zircon. Deformed, normally graded vitric beds; sharply defined basal contact with underlying loess. Lowermost 20 cm of tephra is very pure, the uppermost 5 cm consists of reworked tephra and loess. From Preece et al. (2011): bubble-wall shards, trace amounts of brown glass; in silt; field name SC-T References:  Dawson Tephra: a prominent stratigraphic marker of late Wisconsinan age in west-central Yukon, Canada A catalogue of late Cenozoic tephra beds in the Klondike Goldfields and adjacent areas, Yukon Territory Old Crow tephra across eastern Beringia: a single cataclysmic eruption at the close of Marine Isotope Stage 6 |
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