Diana Elizabeth Fernández

• PhD
• Researcher at University of Buenos Aires

Lower Cretaceous trackways assignable to xiphosurids were recently found in tidally influenced marginal-marine deposits of the Agrio Formation (Patagonia, Argentina). The aim of this paper is to describe these trace fossils in detail, discuss their conditions of preservation, make palaeoecological and taphonomic inferences from them, and analyse th...

Paleontology in Argentina has a long history. The first fossil discoveries date back to the mideighteenth century. The progress made in recent years indicates that the discipline continues to grow in the country and has promising future prospects. Given than most of the scientific research done in Argentina is funded by government agencies, the fut...

Most stellate trace fossils of the ichnogenus Asteriacites are attributed to asterozoan producers in general and the majority is the result of the work of ophiuroids. The fossil record of asterozoans is scarce in South America, particularly for the Mesozoic. Asteriacites specimens found in shallow- to marginal-marine Lower Cretaceous (upper Hauteri...

Polychaetes, echinoids and gastropods have been proposed as tracemakers for Bolonia Meunier, an elongate positive epirelief trace fossil characterized by two lobes composed of biserial, subtriangular pads and a mostly heartshaped cross-section. Here, the internal structure and micromorphology of Bolonia are described for the first time using serial...

Bioerosion is a valuable tool for inferring palaeoenvironmental and palaeoclimatic changes over time and across different regions. However, studies of bioerosion traces are scarce in the Southern Hemisphere. Most ichnological studies within Argentina are concentrated in San Jorge Gulf (Patagonia, Argentina) and little is known about deposits locate...

Ichnology is an important tool for palaeoenvironmental analysis. The first part of this chapter includes a brief review about the development of ichnology as a science, followed by some basic concepts about trace fossils and biogenic sedimentary structures, including their formation and description. Posteriorly the basis of the different proposals...

Evidence of durophagous predatory behavior on benthic invertebrates in the Upper Jurassic-Lower Cretaceous of the Neuquén Basin is scarce, despite the abundant record of potential predators. Herein, we document shell repair in one gastropod from lower Barremian marginal-marine deposits in northern Neuquén Basin, Argentina. This is the first report...

Several elongated and other crescent-shaped impressions interpreted as dinosaur tracks and preserved on Lower Cretaceous tidal flat deposits from the Agrio Formation (northern Patagonia, Argentina) are studied in detail. These tracks were documented on a paleosurface showing paleotopographic differences over a short distance, related to the lateral...

The Río Seco de los Castaños Formation (San Rafael Block) holds one of the few middle Palaeozoic (Silurian−Devonian) records worldwide of a Nereites-Dictyodora dominated ichnofauna with sedimentological features such as oscillatory and combined-flow deposits. This record is associated with microbial mats in fine-grained intervals between turbidite-...

The last review of Asteriacites (Knaust and Neumann 2016) dismissed sculpture as an ichnotaxobase for this ichnogenus and used simple morphometric parameters to differentiate the ichnospecies, reducing them to three: A. lumbricalis, A. stelliformis, and A. quinquefolius. In this work, ichnotaxonomic tools are discussed through the analysis of trace...

The Lower Cretaceous Agrio Formation is a source rock considered to be a possible unconventional reservoir. However, no detailed microstructure characterization of this hydrocarbon play has been performed. An exceptional oil-prone level is determined through outcrop information, petrography, x-ray diffraction, geochemical analysis, and x-ray micro–...

The Agrio Formation (late Early Valanginian–earliest Barremian) is an environmentally complex marine and continental succession that involves unconformities and flooding surfaces that respond to tectonic thermal subsidence. Internally, the Pilmatué Member contains five third-order sequences eustatically controlled. The Avilé Member starts over a re...

Gregarious behaviour among dinosaurs has been inferred from several lines of evidence (monospecific bonebeds, skeletal morphology, phylogenetic inferences, comparison with modern ecosystems and parallel trackways with particular characteristics), but is relatively poorly documented for non-avian theropods. Here, we report five parallel theropod tra...

Gregarious behaviour is an important aspect of dinosaur paleoecology and has been inferred from several evidences: monospecific bonebeds, skeletal morphology, phylogenetic inferences, comparison with modern ecosystems and parallel trackways. Nevertheless, it is relatively poorly documented and understood among non-avian theropods. In the Cenomanian...

The Agua de la Mula Member (Upper Hauterivian–Lower Barremian) of the Agrio Formation represents the infill of a mixed siliciclastic–carbonate low-gradient ramp system comprising both hydrocarbon sand reservoirs and a source rock interval considered as potential unconventional shale play. The present study analyzes the unit in offshore settings (Lo...

The first articulated remains of ophiuroids for the Mesozoic of South America are described from the Lower Cretaceous of Neuquén Basin, Argentina. The taxonomic analysis allows the assignment of the material described herein to the extinct genus Ophiopetra. The specimens belong to a new species, but considering the poor preservation, a new name is...

Dinosaurs are extremely abundant in the Upper Cretaceous Neuquén Group of the Neuquén Basin (Argentina). Nevertheless, while osteological remains are rich the ichnological record is more restricted. A new sauropod dinosaur trackway with five manus-pes imprint sets discovered in the Cenomanian Candeleros Formation is described here. The trackway bel...

Sedimentitas del Miembro La Tosca de la Formación Huitrín en dos localidades del sur de Mendoza preservan el primer caso documentado de predación por durofagia sobre conchillas de gastrópodos del Cretácico Inferior de la Cuenca Neuquina. El caso de estudio involucra dos conjuntos de conchillas de una misma especie, Paleoanculosa macrochilinoides (D...

Bolonia lata Meunier in Lower Cretaceous shallow marine facies from Patagonia: ichnotaxonomic implications

Taxonomic analysis of the first ophiuroid remains for the Mesozoic of South America: the youngest record of the extinct genus Ophiopetra Hess

The lowermost part of the Agua de la Mula Member (upper Hauterivian), Agrio Formation, was studied in distal depositional settings at four locations in the central Neuquén Basin. Detailed sedimentological and ichnological analysis combining field data and microfacies, using petrography, X-ray diffraction, and organic geochemical data allow to recog...

La Formación Balcarce presenta una serie de cuestiones estratigráficas que permanecen no resueltas, tanto referidas a su definición como a la correlación con unidades de África. El análisis de información composicional, relaciones de campo y paleocorrientes permiten descartar una continuidad entre las diamictitas hirnantianas y las clásicas ortocua...

Herradurichnus Poiré & del Valle, 1996 from the Balcarce Formation (lower Paleozoic of the Tandilia System, Argentina) is an enigmatic ichnogenus previously considered as problematic. In this paper, Herradurichnus is revised and key material from collections is redescribed together with other specimens documented in situ from outcrops and quarries....

Cuadernillo “Detectives del Pasado” para el Ministerio de Educación de la Nación Argentina. Dirección Nacional de Políticas Socioeducativas. Programa Nacional de Extensión Educativa

Cuando hablamos de los fósiles o de las montañas, parece que tenemos claro que se formaron hace “mucho tiempo”. Decimos que algo ocurrió hace miles o millones de años. Sin embargo, cabe preguntarse si verdaderamente comprendemos esas cantidades de tiempo o si tenemos noción de cuánto tiempo involucran los procesos de formación de los fósilesy las m...

Los cuadernillos de Popularización de la Ciencia surgen como parte de una estrategia de acompañamiento y capacitación y pretenden constituirse como material de apoyo de la Orientación Ciencia de los Centros de Actividades Juveniles (CAJ). En ellos se proponen talleres con actividades en los que se transitan los "modos de hacer" de la ciencia y se p...

La icnología como ciencia estudia el registro de la actividad de organismos e infiere su comportamiento. La misma tiene por un lado, un abordaje netamente paleontológico que atañe a aspectos sistemáticos y de los productores de icnofósiles y por otro, muchas veces inadecuadamente tratado, que tiene consecuencias en las asignaciones icnotaxonómicas...

Comunidad de aprendizaje y efecto multiplicador intra-universitario: un ejemplo de líneas de acción y actividades de extensión interdepartamentales de alumnos, docentes e investigadores de la FCEyN-UBA

Manual de educación primaria. Editorial MacMillan-Estrada

The association of trace fossils from the late Silurian Río Seco de los Castaños Formation in central-western Argentina (San Rafael Block) is mainly composed of Dictyodora, including D. scotica, D. tenuis and a new ichnospecies named D. atuelica. The latter shows a tendency to migrate to a deeper level – analogous to D. liebeana’s – which reflects...

In-depth ichnological studies of Lower Cretaceous, marginal-marine facies from the Ag-rio Formation (Patagonia, Argentina) have been carried out during the past few years. Several ich-nofossils were identified and described for the first time in this unit, including a new ichnospecies (Hillichnus agrioensis) produced by tellinid bivalves, xiphosuri...

During the past few years, the first integrated ichnological/sedimentological research of Lower Cretaceous, marginal-marine units from the Neuquén basin (Northern Patagonia, Argentina) has been carried out. Most of the ichnofossils included in those studies were invertebrate trace fossils. Only some were assigned to vertebrates (non-avian theropod...

Implications of recently found Early Cretaceous xiphosurid trackways from the Neuquén basin (Western Gondwana): evidence of paleocoastline continuity?

Ichnological research in Lower Cretaceous marginal-marine facies from Patagonia: outcrop studies, SEM examinations, and paleontological/sedimentological integration

Asterozoans are free living, star-shaped echinoderms which are important components of benthic marine faunas worldwide. Their fossil record is, however, poor and fragmentary, probably due to dissarticulation of ossicles. In particular, fossil asteroids are infrequent in South America. A new species of starfish is reported from the early Valanginian...

Ichnological study of the Lower Cretaceous Mulichinco Formation (Neuquén Basin, northern Patagonia): preliminary results

Asteroid trace fossils from a Lower Cretaceous shallow marine paleoenvironment in Patagonia: the first record of starfishes for the Agrio Formation

Icnología de facies marino-marginales en el Cretácico Inferior de la cuenca Neuquina

This study includes a thorough systematic analysis of the ichnological record in the uppermost section of the Agua de la Mula Member of the Agrio Formation (Mendoza Group) in the Neuquen Basin (Argentina). The Bajada del Agrio section represents an environment evolving from marine to marginal-marine. Five main facies were defined: (1) an oolitic-sk...

From outcrop studies up to SEM examinations: integrated ichnological/sedimentological research of Lower Cretaceous, marginal-marine units from northern Patagonia

The study of the uppermost section of the Early Cretaceous Agrio Formation in northern Patagonia (Neuquén Basin) where dinosaur tracks assigned to cf. Therangospodus pandemicus are exposed (tracksites I and II) evidence mixed marginal marine siliciclastic-carbonate deposits. The succession was divided in two intervals. A lower one containing therop...

Nereites-like Trace Fossils in Lower Cretaceous Marginal Marine Environments from Patagonia: Preservational Variants and Ichnotaxonomic Discussion

Enhanced Preservation of Delicate Arthropod Trackways by Microbial Mat Biostabilisation in a Cretaceous Marginal-Marine Setting from Patagonia: A Preliminary Study

Primer registro corpóreo articulado de ofiuroideos (Echinodermata: Asterozoa: Ophiuroidea) para el Mesozoico de América del Sur

Preliminary study of an astropectinid (Asteroidea; Echinodermata) from the Lower Cretaceous (Mulichinco Formation) of the Neuquén Basin, Argentina

As a result of a microfacial study in the outer and middle ramp deposits of the Vaca Muerta Formation (lower Tithonian-upper Valanginian), four ichnotaxa of crustacean microcoprolites are described: Palaxius azulensis Kietz− mann isp. nov., Palaxius caracuraensis Kietzmann isp. nov., Helicerina? isp. A. aff. Helicerina siciliana and Helicerina isp....

This study focuses on the description of a compound trace fossil from the Cretaceous of the Neuquén Basin, Argentina. This structure comprises two discrete ichnotaxa: Protovirgularia cf. dichotoma M’Coy, 1850, and Protovirgularia cf. rugosa (Miller and Dyer, 187823. Miller , S. A. and Dyer , C. B. 1878 . Contributions to paleontology . Journal of t...

Acomplex trace fossil that requires a three-dimensional (3D) reconstruction is described and interpreted. The specimens studied are assigned to a new ichnospecies (Hillichnus agrioensis) of Hillichnus Bromley et al., 2003.Most of them are uncollectable and a compound iconotype was designed to characterise the new ichnospecies. The three-dimensional...

As a result of a microfacial study in the outer and middle ramp deposits of the Vaca Muerta Formation (lower Tithonian-upper Valanginian), four ichnotaxa of crustacean microcoprolites are described: Palaxius azulensis Kietzmann isp. nov., Palaxius caracuraensis Kietzmann isp. nov., Helicerina? isp. A. aff. Helicerina siciliana and Helicerina isp. B...

Los ambientes transicionales resultan particularmente interesantes al momento de realizar un estudio de trazas fósiles, ya que presentan una alta complejidad sedimentológica en la organización de facies, y los icnofósiles pueden resultar de gran importancia para delinear variaciones faciales. Numerosos estudios publicados han mencionado la presenci...