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Barda Negra 1 (Miocene of Argentina)

Also known as BN1

Where: Neuquén, Argentina (39.0° S, 69.7° W: paleocoordinates 39.8° S, 64.2° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Cerro Bandera Formation, Colhuehuapian (21.0 - 17.5 Ma)

• Kramarz et al. (2005) concluded that the fossil- bearing deposits of the Cerro Bandera Formation correlate with the Lower Faunal Zone in the Colhue Huapi Member of the Sarmiento Formation at Gran Barranca (south of Colhue Huapi Lake, central Patagonia), dated at 21.1–20.1 Ma (Dunn et al., 2013), the type section for the Colhuehuapian South American Land Mammal Age (SALMA).

• group of beds-level stratigraphic resolution

Environment/lithology: fluvial; paleosol/pedogenic, bentonitic, tuffaceous volcaniclastic sediments

• The Cerro Bandera Formation is 45 m-thick and consists

•of pyroclastic deposits showing evidence of fluvial rework- ing and/or pedogenesis, alternating with primary fall-out pyroclastic deposits, with abundant bentonitic horizons in the lower section and scant intercalated sandstones in the upper section. The abundant tuffaceous and tuffitic con- tents would have originated from discontinuous ash fall derived from Andean or sub-Andean volcanic centers. The origin of these deposits is associated with a fluvial environ- ment in an intermontane foreland basin; lacustrine deposits accumulated in the central, topographically lower areas of the paleovalleys, whereas paleosols accumulated in the marginal, higher areas. This depositional system resulted in marked lateral facies variations among the currently isolated exposures (Leanza and Hugo, 1997; Kramarz et al., 2005).

Size class: mesofossils

Collected in 2015; reposited in the MACN, MLP

Primary reference: A. G. Kramarz, M. G. Vucetich, and M. Arnal. 2013. A new Early Miocene chinchilloid hystricognath rodent; an approach to the understanding of the early chinchillid dental evolution. Journal of Mammalian Evolution 20:249-261 [J. Zijlstra/J. Zijlstra/P. Mannion] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 89028: authorized by Darin Croft, entered by Darin Croft on 29.04.2009, edited by Juan Carrillo, Jelle Zijlstra and Miranta Kouvari

Creative Commons license: CC BY (attribution)