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USGS · 70016766

First early Mesozoic amber in the Western Hemisphere

R. J. Litwin·S.R. Ash
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Abstract

Detrital amber pebbles and granules have been discovered in Upper Triassic strata on the Colorado Plateau. Although amber pre-viously has been reported from Pennsylvanian, Jurassic, Cretaceous, and Tertiary strata, we know of no other reported Triassic occurrence in North America or the Western Hemisphere. The newly discovered occurrences of amber are at two localities in the lower part of the Petrified }Forest Member of the Upper Triassic Chinle Formation in Petrified Forest National Park, Arizona. The paper coals and carbonaceous paper shales containing the amber also contain fossil palynomorph assemblages that indicate a late Carnian age for these occurrences.

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R. J. Litwin, S.R. Ash. 1991. First early Mesozoic amber in the Western Hemisphere. https://doi.org/10.1130/0091-7613(1991)019%3C0273%3Afemait%3E2.3.co%3B2

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