A5082182375- Evolution and Paleontology Studies
- Paleontology and Evolutionary Biology
- Paleontology and Stratigraphy of Fossils
- Geological formations and processes
- Geology and Paleoclimatology Research
- Ichthyology and Marine Biology
- Plant Diversity and Evolution
- Geological and Geochemical Analysis
- Geological and Tectonic Studies in Latin America
- Hydrology and Sediment Transport Processes
- Plant and Fungal Species Descriptions
- Environmental and Ecological Studies
- Soil erosion and sediment transport
- Hydrocarbon exploration and reservoir analysis
- Geological and Geophysical Studies Worldwide
- Geological and Geophysical Studies
- Botany, Ecology, and Taxonomy Studies
- Groundwater and Isotope Geochemistry
- Fish biology, ecology, and behavior
- Pleistocene-Era Hominins and Archaeology
- Urbanism, Landscape, and Tourism Studies
- Turtle Biology and Conservation
- Cephalopods and Marine Biology
- Geochemistry and Geologic Mapping
- Water Resource Management and Quality
Consejo Nacional de Investigaciones Científicas y Técnicas
2008-2024
National University of San Juan
2014-2024
Centro Científico Tecnológico - San Juan
2011-2020
Centro Científico Tecnológico - Tucumán
2008-2019
University of Buenos Aires
2008
Two hundred thirty million years ago, in what is now Argentina, dinosaurs could be found as the dominant carnivores or small herbivores.
ABSTRACT The Upper Triassic (Carnian–Norian) Ischigualasto Formation has yielded a diverse vertebrate fauna that records the initial phase of dinosaur evolution. Radioisotopic dates from ash layers within formation provide chrono- stratigraphic framework, and sedimetological studies have subdivided into four members three abundance-based biozones. We describe two new basal dinosauromorphs, an unnamed lagerpetid silesaurid, Ignotosaurus fragilis, gen. et sp. nov., which increase to 29 number...
Significance Uncertainties in reported 40 Ar/ 39 Ar dates from the Ischigualasto Formation of Argentina allow its dinosaur-bearing fauna to be Norian age and possibly contemporaneous with some older U-Pb dated units Chinle American Southwest. Our magnetochronology previously undated Los Colorados Formation, which also contains a diverse dinosaur assemblage, constrains interval 227 213 Ma (Norian) thereby largely restricts underlying Carnian. Rise early dinosaurs was thus diachronous across...
Dinosauria debuted on Earth’s stage in the aftermath of Permo-Triassic Mass Extinction Event, and survived two other Triassic extinction intervals to eventually dominate terrestrial ecosystems. More than 231 million years ago, Upper Ischigualasto Formation west-central Argentina, dinosaurs were just getting warmed up. At this time, represented a minor fraction ecosystem diversity. Members tetrapod clades, including synapsids pseudosuchians, shared convergently evolved features related...
The Ischigualasto Formation was deposited in a fluvial system and contains very well preserved Triassic flora. This flora comprises seven taphofacies: (1) C(St), autochthonous silicified roots of low-statured, woody plants associated with low-sinuosity channels crevasse-splay deposits; (2) A(Sm/Fm), carbonized or root impressions herbaceous levee (3) B(Fsm/Fm), halos (4) EI(St), allochthonous tree trunks charcoal high- channel bars; (5) GI(St), leaf cuticles trough cross-bedded sandstone;...
Sphenodontians were a successful group of rhynchocephalian reptiles that dominated the fossil record Lepidosauria during Triassic and Jurassic. Although evidence extinction is seen at end Laurasian Early Cretaceous, they appeared to remain numerically abundant in South America until period. Most known Late Cretaceous composed opisthodontians, herbivorous branch Sphenodontia, whose oldest members recently reported be from Kimmeridgian–Tithonian (Late Jurassic). Here, we report new...
The Quebrada del Barro Formation (QBF) is part of the continental Marayes-El Carrizal Basin, in NW Argentina. Here we report a diverse faunal assemblage recently discovered Formation, along with preliminary discussion taxonomic status and affinities numerous vertebrate specimens found at two localities where this unit exposed. new association includes remains least 12 different species related to six major groups: Cynodontia, Testudinata, Sphenodontia, Pseudosuchia, Pterosauria,...
Large-diameter ichnofossils comprising three morphotypes have been identified in the Upper Triassic Ischigualasto and Los Colorados formations of northwestern Argentina. These burrows add to global record early appearance fossorial behavior during Mesozoic time. Morphotypes 1 2 are characterized by a network tunnels shafts that can be assigned tetrapod given similarities with previously described forms. However, differences diameter, overall morphology, stratigraphic occurrence allow their...
Abstract This study investigates the potential of laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) U‐Pb dating for carbonate nodules in Late Triassic Ischigualasto Formation northwestern Argentina. We establish a fully characterized paragenetic sequence to guide analysis three pedogenic carbonates and compare ages with published geochronology from volcanic ashes within sedimentary succession. Our findings demonstrate importance interpreting data well‐defined framework...
Coprolites were collected 74 m above the base of Upper Triassic Ischigualasto Formation northwestern Argentina and their chemistry, mineralogy, textures studied to infer biological source taphonomy. They found contain a few fragments bone much crystalline apatite, so can be assigned carnivores able digest bone. Primary minerals derived from endogenous materials apatite pyrite, secondary ground water chiefly calcite glauconite in one coprolite another. presumed originally have been mostly...
ABSTRACT Trends of preservation are established on the basis 385 fossil occurrences in Ischigualasto Formation. The distribution and preservational quality vertebrate fossils related to sedimentary facies stratigraphic position follow trends basin evolution paleoclimate. Fossils Formation mainly concentrated along margins basin. Floodplain deposits preserve ca. 88% fossils, which range from unidentifiable fragments articulated skeletons. remaining (ca. 12%) come coarser-grained fluvial...
ARGENTINA: PALEOATMOSPHERIC IMPLICATIONS.The Upper Triassic Ischigualasto Formation carries a well-preserved flora in the mid-upper portion (~225 Ma Carnian).This contribution is first detailed study of isotopic ratios (i.e. 13 Carbon vs. 12 δ C) and ratio carbon nitrogen (C/N) applied to Argentinean flora.The aim this chemically characterize provide data for Pangea be used chemostratigraphic correlation as well analyze changes global cycle.A total 97 samples were analyzed, mainly...
Abstract Clam shrimps are a group of freshwater crustaceans who prospered during the Late Triassic. They were abundant in lacustrine sedimentary records continental basins distributed throughout Pangea this time. However, they show significant taxonomic differences between clamp shrimp faunas from rift central and southern Gondwanan basins. In contribution, we new fossil clam assemblages successions Eastern Cordillera Colombia (the Bocas Montebel formations), providing information on...
The northern area of Cuyo Basin (west‐central Argentina) corresponds to the Rincón Blanco half-graben, whose filling is arranged into and Sorocayense groups. In present study, we propose a new stratigraphic scheme for Group in Barreal depocenter (San Juan Province), revise palaeoenvironmental interpretations, organize analyse plant assemblages previous fossiliferous levels. We defined three tectosedimentary sequences. basal sequence represents initial graben with pyroclastic flows, alluvial...
ABSTRACT The last stage of activity the Ischigualasto–Villa Unión Rift Basin in west-central Argentina is represented by 1100-m-thick fluvial red-beds Los Colorados Formation (Norian). Facies and architectural-element analysis were applied vertical stacking patterns evaluated to develop a depositional model for postrift basin fill. subdivided into eleven stratigraphic intervals, generally characterized multistory multilateral channelized bodies interspersed with thick floodplain deposits...