The Malargüe Group is a group of geologic formations of the Neuquén Basin of the Mendoza, Neuquén, Río Negro and La Pampa Provinces in northern Patagonia, Argentina. The formations of the Malargüe Group range in age between the middle Campanian to Deseadan, an Oligocene age of the SALMA classification, straddling the Cretaceous–Paleogene boundary, about 79 million to 30 million years in age. The group overlies the older Neuquén Group, separated by an unconformity dated to 79 Ma.Leanza et al., 2004, p.63 The rocks of the Malargüe Group comprise both marine and continental deposits which are over 400 m (1312 ft) thick in total.

Subdivision The Malargüe Group is subdivided into: Agua de la Piedra Formation (Deseadan) - white-grayish tuffs and tobaceous paleosolsAgua de la Piedra Formation at Fossilworks.org Roca Formation (Maastrichtian to Danian) - coastal mudstones and sandstonesRoca Formation at Fossilworks.org Jagüel Formation (middle Maastrichtian to Danian) - shallow marine mudstonesJagüel Formation at Fossilworks.org Loncoche Formation (late Campanian to early Maastrichtian) - terrestrial conglomerates and sandstones, delta plain sandstones and limestonesLoncoche Formation at Fossilworks.org Allen Formation (middle Campanian to early Maastrichtian) - eolian sandstones and fluvio-lacustrine mudstones and limestones

Fossil content

Fossils of dinosaurs, plesiosaurs, turtles (Euclastes,Euclastes at Fossilworks.org Mendozachelys wichmanni),De la Fuente et al., 2017 Paleoanculosa sp.,Previtera & González Riga, 2008 fish,Gónzalez Riga, 1999 birds (cf. Andrewsornis sp.) and mammals have been recovered from the strata that make up the Malargüe Group.Weishampel et al., 2004

Mammals of the Agua de la Piedra Formation Archaeohyrax suniensis, Argyrohyrax proavus, Asmodeus petrasnerus, Fieratherium sorex, Gualta cuyana, Hegetotheriopsis sulcatus, Mendozahippus fierensis, Meteutatus aff. lagenaformis, Proborhyaena gigantea, Prohegetotherium malalhuense, P. schiaffinoi, P. cf. sculptum, Propachyrucos cf. smithwoodwardi, ?Prozaedyus aff. impressus, Pyrotherium romeroi, Stenotatus aff. ornatus, Trachytherus cf. spegazzinianus, cf. Archaeotypotherium sp., Pharsophorus sp., Proadinotherium sp., Progaleopithecus sp., cf. Prosotherium sp., Acaremyidae indet., Glyptodontidae indet., Interatheriidae indet., Litopterna indet., ?Megalonychidae indet., Notohippidae indet., Toxodontidae indet.Quebrada Fiera at Fossilworks.orgCerdeño & Reguero, 2015Seoane & Cerdeño, 2014Cerdeño & Vera, 2014

See also

List of fossil sites Santa Lucía Formation, Maastrichtian to Danian (Tiupampan) fossiliferous formation of the Potosí Basin, Bolivia Yacoraite Formation, Maastrichtian to Danian fossiliferous formation of the Salta Basin López de Bertodano Formation, Maastrichtian to Danian fossiliferous formation of northern Antarctica

References

Bibliography Cretaceous

Paleogene