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The Paris Agreement established global ambitious targets for reducing carbon dioxide (CO2) emissions, requiring the rapid and extensive development of low carbon technologies, and one of the most efficient is CO2 geological storage. Among the deep geological formations used for CO2 storage, the shale layers have been a new emerging field with higher efficiency because they are abundant and have a high content of organic matter that is favorable for CO2 retention. However, one of the challenges in evaluating a location for potentials reservoirs is the adequate geological characterization and storage volume estimation. The study evaluates the Irati Formation of the Paraná Basin based on wireline logs information within Southeastern Brazil, where most stationary sources of carbon emissions are located. Three‐dimensional (3D) implicit modeling techniques were applied not only for volume calculation purpose, but also in the site selection stage, generating thematic 3D models indicating thickness, depth, structures, and distance to aquifer systems. The limestones, shales, and black shales of the Irati Formation were locally grouped into six units considering the geological composition and spatial continuity. Based on the 3D model and reservoir parameters, the organic‐rich shale Unit E with a theoretical capacity of 1.85 Gt is considerable for CO2 storage. The estimated CO2 storage capacity is promising because it is higher than the total CO2 locally produced, and it could support the implantation of new projects in this region. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This work presents fission-track ages and thermal history modelling of apatite samples from two Brazilian alkaline formations: Alto Paranaíba and Ponta Grossa Arches. The apatite fission-track ages obtained for Alto Paranaíba Arch agree with those determined by other radiometric dating methods presenting higher closure temperatures. The ages given by the fission-track thermochronometer suggest that no strong tectonic event has occurred after Alto Paranaíba Formation during Upper Cretaceous. This event is also supported by thermal history modelling of this arch, which is characterized by fast cooling followed by residence at lower temperatures. On the other hand, apatite fission-track ages from Ponta Grossa Arch are systematically lower than other radiometric ages, suggesting that at least one tectonic event occurred after Ponta Grossa Formation, around 130 Ma. [ABSTRACT FROM AUTHOR]

The first dicynodont reported for the Permian of South America is described in detail here. The specimen consists of a partial skull and associated lower jaws, collected from the Serra do Cadeado locality, Rio do Rasto Formation, Brazil. The specimen was assigned to the genus Endothiodon Owen in a preliminarily description published in the 1970s. This identification implied a direct correlation with some of the well-established biozones of the Beaufort Group, South Africa, where this taxon is known to occur. Although badly weathered, the Brazilian material preserves several features that allow us to confirm its assignment to Endothiodon, such as the pineal foramen situated on a boss, the bulbous swellings of the dentaries, a boss situated on the ventral margin of the jugal, the extensive number of dentary teeth and the upturned pointed beak of the lower jaw. However, this set of characters is not enough to establish a specific taxonomic assignment for the specimen, although it seems to be more closely related to E. bathystoma, E. uniseries and E. whaitsi than to E. mahalanobisi. The biostratigraphical correlations proposed for the tetrapod faunas of the Rio do Rasto Formation highlight the similarities between these associations and others from the Mid and Late Permian of South Africa and Eastern Europe. However, until now, these correlations are tentative because only a few faunal elements have been recovered from Brazil, and most of them lack stratigraphic data on the levels from where they were collected. Due to the presence of Endothiodon, at least part of the Rio do Rasto Formation can be correlated with deposits in India, Malawi, Mozambique, South Africa, Tanzania, Zambia and Zimbabwe. [ABSTRACT FROM AUTHOR]

Leonardosia Sommer is one of the scarce Permian charophyte genera and is part of the lineage that may include the ancestors of the post-Palaeozoic families. Oospores of the species Leonardosia langei Sommer have been found in strata of the Teresina Formation, Paraná Basin, Southern Brazil, where they are preserved as compressions. The charophyte organs found in this formation, including the original description of Leonardosia have been previously been interpreted as gyrogonites despite the presence of a carbonaceous film. We propose that these charophyte organs and the fructifications should be re-interpreted as organic oospores rather than gyrogonites. The coiling pattern, in most cases, proved to be reverse as a result of the compression of the oospore against the internal wall of the dissolved gyrogonite. In some cases, the coiling was ambiguously observed in both directions by an overlap of the opposite walls of the oospore and the dissolved gyrogonite. A simple basal plate for L. langei was registered, and its relation with the main ideas about the phylogeny and the evolution of Mesozoic charophytes is also discussed. The 'Stellatocharoideae' is polyphyletic including both the stem lineage of the Nitellaceae, represented by the multipartite basal plate genera, and a clade that belongs to the evolutionary line of the Monoplacata, represented by Leonardosia. [ABSTRACT FROM AUTHOR]

Despite the generalized occurrence of colluvial deposits in the humid tropical areas of southeastern Brazil, regional correlation is difficult because the deposits are discontinuous, and chronological data are very scarce and scattered. For the first time, colluvial deposits in the Bocaina Plateau are described, including 18 radiocarbon ages from 12 profiles. The plateau is located on the eastern flank of the Continental Rift of Southeastern Brazil and is the highest part of the Serra do Mar, with elevations up to 2000 m above sea level. Because the Bocaina Plateau is part of the summit surfaces of southeastern Brazil, it was subjected to specific climatic conditions during the Quaternary. Colluvial deposits on the lower hillslopes and edges of amphitheatres can show complex sequences with up to three intercalated dark humic horizons, corresponding to Late Pleistocene and Holocene phases of morphodynamic activity and pedogenesis. Ages of palaeosols vary from 650±50 a BP to 36 880±980 a BP. Landforms and colluvia on the Bocaina Plateau are very similar to those found on the opposite flank of the continental rift, on the Campos do Jordão Plateau. Ages of buried soils point to similar soil formation and colluviation episodes in the two plateaus. As in Campos do Jordão, the succession of erosive, depositional and pedogenetic processes on the altos campos hillslopes is probably related to late Quaternary climate changes. [ABSTRACT FROM AUTHOR]

Open-coast tidal flats are hybrid depositional systems resulting from the interaction of waves and tides. Modern examples have been recognized, but few cases have been described in ancient rock successions. An example of an ancient open-coast tidal flat, the depositional architecture of the Lagarto and Palmares formations (Cambrian-Ordovician of the Sergipano Belt, north-eastern Brazil) is presented here. Detailed field analyses of outcrops allowed the development of a conceptual architectural model for a coastal depositional environment that is substantially different from classical wave-dominated or tide-dominated coastal models. This architectural model is dominated by storm wave, low orbital velocity wave and tidal current beds, which vary in their characteristics and distribution. In a landward direction, the storm deposits decrease in abundance, dimension (thickness and spacing) and grain size, and vary from accretionary through scour and drape to anisotropic hummocky cross-stratification beds. Low orbital wave deposits are more common in the medium and upper portion of the tidal flat. Tidal deposits, which are characterized by mudstone interbedded with sandstone strata, are dominant in the landward portion of the tidal flat. Hummocky cross-stratification beds in the rock record are believed, in general, to represent storm deposits in palaeoenvironments below the fair-weather wave base. However, in this model of an open-coast tidal flat, hummocky cross-stratification beds were found in very shallow waters above the fair-weather wave base. Indeed, this depositional environment was characterized by: (i) fair-weather waves and tides that lacked sufficient energy to rework the storm deposits; (ii) an absence of biological communities that could disrupt the storm deposits; and (iii) high aggradation rates linked to an active foreland basin, which contributed definitively to the rapid burial and preservation of these hummocky cross-stratification deposits. [ABSTRACT FROM AUTHOR]

A new rhynchosaur,Hyperodapedon hueneisp. nov., is described from the Upper Triassic Santa Maria Formation of the Paraná Basin, Brazil. The holotype is an almost complete skull and mandible, collected at Inhamandá, in the state of Rio Grande do Sul, Brazil. The diagnosis of the genusHyperodapedonHuxley is revised to include not onlyH. huxleyiLydekker andH. gordoniHuxley (as generally accepted), but also the new species described here, various specimens usually assigned to 'Scaphonyx fischeri' Woodward, and 'S'.sanjuanensisSill.H. hueneisp. nov. exhibits a number of plesiomorphic features and appears to be the least derived species ofHyperodapedon, forming a sister taxon to the remaining members of the genus. A preliminary phylogenetic analysis for the more derived rhynchosaurs is presented. 'Scaphonyx'sulcognathusAzevedo and Schultz represents the sister taxon ofHyperodapedon, while 'Rhynchosaurus'spenceriBenton is considered to be a more derived Middle Triassic rhynchosaur.key words: Rhynchosauria,Hyperodapedon, Triassic, Brazil. [ABSTRACT FROM AUTHOR]