Also known as Cifuentes or de Aldaya, 2.85 km downstream from RN3

Where: Buenos Aires, Argentina (38.6° S, 60.6° W: paleocoordinates 38.7° S, 59.5° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Irene Formation, Early/Lower Pliocene (5.3 - 3.6 Ma)

• Prevosti et al. 2021: On analysis, one aliquot of a sample from QSLo (lower Quequén Salado, Paso del Halcón) presented extensive evidence of excess argon in the first half of the spectrum, but the final steps representing about 50% of released 39Ar yielded an age of 5.17 ± 0.08 Ma. A single aliquot of a sample from QSUp (upper Quequén Salado, Cascada Grande) gave an age of 4.33 ± 0.06 Ma. Our results close almost a century of argument concerning the relative antiquity of the “Irenean”( Kraglievich 1934, Goin et al. 1994, Pardiñas et al. 2017, Beilinson et al. 2017). The controversial lower fauna from the Quequén Salado River can now be shown to be of Zanclean age (5.17 Ma) and thus well within the Early Pliocene. Its upper fauna is also Early Pliocene (4.33 Ma), a point previously unclear.

Environment/lithology: terrestrial; massive, calcareous siltstone

Size class: macrofossils

Reposited in the MLP

Primary reference: U. F. J. Pardinas, F. J. Prevosti, D. Voglino and M. Cenizo. 2017. A controversial unit within the argentine neogene: the “Irenean” fauna. Ameghiniana 54(6):655-680 [E. Vlachos/E. Vlachos]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 191764: authorized by Evangelos Vlachos, entered by Evangelos Vlachos on 14.02.2018, edited by Kateryn Pino

Creative Commons license: CC BY (attribution)