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Independent time markers validate Pb-210 chronologies for two shallow Argentine lakes in Southern Pampas
(Pergamon-Elsevier Science Ltd, 2016-08)
We report here the results of detailed 210Pb analysis from two lake sediment cores collected from Lagunas Encadenadas del Oeste (LEO), located in the southern Argentinean Pampas (37°S, 62°W). Non-exponential and non-monotonic ...
A Late Eocene date for Late Triassic bird tracks
(Nature Publishing Group, 2013-03)
Bird-like tracks from northwest Argentina have been reported as being of Late Triassic age1. They were attributed to an unknown group of theropods showing some avian characters. However, we believe that these tracks are ...
The Chachil Limestone (Pliensbachianeearliest Toarcian) Neuquén Basin, Argentina: UePb age calibration and its significance on the Early Jurassic evolution of southwestern Gondwana
(Pergamon-elsevier Science Ltd, 2013-06)
New radiometric UePb ages obtained on zircon crystals from Early Jurassic ash layers found within beds of the Chachil Limestone at its type locality in the Chachil depocentre (southern Neuquén Basin) confirm a Pliensbachian ...
New U–Pb zircon age for the Pennsylvanian in Argentina: Implications in palynostratigraphy and regional stratigraphy
(Pergamon-Elsevier Science Ltd, 2019-06)
A continuous Pennsylvanian succession belonging to the Agua Colorada and De La Cuesta formations is exposed in the Las Angosturas area (Catamarca Province) of the Paganzo Basin. Glacial, postglacial, fluvial and shallow ...
New constraints on the Jurassic–Cretaceous boundary in the High Andes using high-precision U-Pb data
(Elsevier Science, 2013-07)
The Jurassic–Cretaceous (J–K) boundary is poorly constrained, and is the only Phanerozoic system boundary that lacks an internationally accepted reference stratigraphic section (GSSP). Precise radio-isotopic U–Pb data are ...
A new Late Triassic age for the Puesto Viejo Group (San Rafael depocenter, Argentina): SHRIMP U-Pb zircon dating and biostratigraphic correlations across southern Gondwana
(Pergamon-Elsevier Science Ltd, 2014-12)
The Puesto Viejo Group crops out in the San Rafael Block, southwest Mendoza, at approximately 35° S and 68°20' W. It consists of the basal mainly grayish Quebrada de los Fósiles Formation (QF) overlying by the reddish Río ...
High resolution isotopic ages for the early Miocene "Patagoniense" transgression in Southwest Patagonia: Stratigraphic implications
(Pergamon-Elsevier Science Ltd, 2012-10)
The classical marine Patagoniense succession at Lago Argentino, southwestern Patagonia (Argentina), known as Estancia 25 de Mayo Formation, was dated by radiometric U-Pb on zircon grains from pyroclastic rocks and 87Sr/ ...
Revised stratigraphic framework of the Cretaceous in the Bajo Grande area (Argentinean Patagonia) inferred from new U–Pb ages and palynology
(Elsevier, 2015-12)
The revision of the stratigraphy of the Cerro Bayo in the Bajo Grande area (Argentinean Patagonia) and the new 206Pb/238U age of 116.85 ± 0.26 Ma constrain the dating of the Baqueró flora, one of the most abundant Aptian ...
Regional implications of U-Pb zircon ages from rhyolitic pebbles of Suncho Formation conglomerates, northern Sierras Pampeanas (NW Argentina)
(E Schweizerbartsche Verlags, 2015-01)
Conglomerates are scarce in the Neoproterozoic/Cambrian strata of the South American Central Andean Basin. In NW Argentina, unusual conglomerates within meta-psammites of the Suncho Formation contain rhyolite clasts that ...
U-Pb zircon age of the Yacoraite Formation and its significance to the Cretaceous-Tertiary boundary in the Salta basin, Argentina
(SCS Publisher, 2011)
Se obtuvieron dos edades U-Pb de circón procedentes de dos capas de ceniza de la Formación Yacoraite (Subgrupo Balbuena, Grupo Salta, Cretácico-Eoceno) de la cuenca de Salta, noroeste de la Argentina. La Formación Yacoraite ...