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Wilf,Peter; Singer,S; Zamaloa,María del Carmen; Johnson,Kirk R; Cúneo,N. Rubén. |
The Pampa de Jones fossil site, a stratigraphically isolated roadcut near the northeastern shore of Nahuel Huapi Lake in Neuquén Province, Argentina, holds a rich fossil biota including a macroflora, a microflora, insects, and most famously, an ontogenetic series of pipid frogs. The site exposes tuffaceous mudstone and sandstone beds of probable lacustrine origin, considered to belong to the volcanic Huitrera Formation. However, there have been no reliable age constraints for the fossil assemblage. We undertook laser fusion analyses of sanidine and biotite crystals occurring in a tuff layer found 4.4 m above the main fossil horizon. Twentyeight sanidine crystals yielded an 40Ar/39Ar age of 54.24 ± 0.45 Ma that is preferred over our biotite age of 53.64 ±... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Early Eocene; Huitrera Formation; Geochronology; Paleobotany; Patagonia; Neuquén; Argentina. |
Ano: 2010 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142010000200006 |
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