Chattermarked garnets and heavy minerals from the Late Paleozoic glacial deposits of southeastern Brazil

1980 ◽  
Vol 17 (1) ◽  
pp. 156-159 ◽  
Author(s):  
C. P. Gravenor
Keyword(s):  
Southern Africa ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Southeastern Brazil ◽  
Late Paleozoic ◽  
Southeastern Part ◽  
Glacial Sediments ◽  
Eastern Side ◽  
Paraná Basin ◽  
Parana Basin

Heavy mineral suites from Late Paleozoic tillites from the southeastern part of the Paraná Basin are dominated by garnet. An analysis of the heavy minerals and chattermark trails found on the garnets suggests that the glacial sediments were transported over long distances, probably as a result of having been recycled many times.The heavy mineral suites are more complex than those found in the intensively glaciated regions of Australia and South Africa. This observation combined with an analysis of the chattermark trails on garnets suggests that glaciation was not as intense nor did it last as long as the glaciation over southern Africa, Antarctica, and Australia. The glaciers which deposited the tillites in the eastern side of the Paraná Basin were probably centered in southern Africa and moved northward and westward penetrating the eastern side of the Paraná Basin.

scholarly journals A new Xenacanthiformes shark (Chondrichthyes, Elasmobranchii) from the Late Paleozoic Rio do Rasto Formation (Paraná Basin), Southern Brazil

2014 ◽  
Vol 86 (1) ◽  
pp. 135-145 ◽  
Author(s):  
VICTOR E. PAULIV ◽  
ELISEU V. DIAS ◽  
FERNANDO A. SEDOR ◽  
ANA MARIA RIBEIRO
Keyword(s):  
New Species ◽  
Longitudinal Section ◽  
Optical Microscope ◽  
Late Paleozoic ◽  
Southern Brazil ◽  
Fossil Assemblage ◽  
Transversal Section ◽  
Paraná Basin ◽  
Parana Basin ◽  
A New Species

The Brazilian records on Xenacanthiformes include teeth and cephalic spines from the Parnaíba, Amazonas and Paraná basins. This work describes a new species of Xenacanthidae, collected in an outcrop of Serrinha Member of Rio do Rasto Formation (Wordian to Wuchiapingian), Paraná Basin, municipality of Jacarezinho, State of Paraná. The teeth of the new species are two or three-cuspidated and the aboral surface show a smooth concavity and one rounded basal tubercle. The coronal surface presents one semi-spherical and subcircular coronal button, and also two lateral main cusps and one central (when present) with less than one fifth of the size of the lateral cusps in the labial portion. The lateral cusps are asymmetric or symmetric, rounded in transversal section, lanceolate in longitudinal section, devoid of lateral carinae and lateral serrations, and with few smooth cristae of enameloid. In optical microscope the teeth show a trabecular dentine (osteodentine) base, while the cusps are composed by orthodentine, and the pulp cavities are non-obliterated by trabecular dentine. The fossil assemblage in the same stratigraphical level and in the whole Rio do Rasto Formation indicates another freshwater record for xenacanthid sharks.

scholarly journals 3D implicit modeling applied to the evaluation of CO2 geological storage in the shales of the Irati Formation, Paraná Basin, Southeastern Brazil

2021 ◽  
Author(s):  
Saulo B. de Oliveira ◽  
Colombo C. G. Tassinari ◽  
Richardson M. A-A. ◽  
Ignacio Torresi
Keyword(s):  
Black Shales ◽  
Hydrocarbon Exploration ◽  
Southeastern Brazil ◽  
Geological Storage ◽  
Spatial Continuity ◽  
Irati Formation ◽  
Aquifer Systems ◽  
Paraná Basin ◽  
Implicit Modeling ◽  
Parana Basin

Abstract 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 topic showing to be efficient because they are abundant and have a high content of organic matter, being favorable for CO2 retention. However, one of the challenges in evaluating a location for possible reservoirs is the adequate geological characterization and storage volume estimates. This research evaluated the Irati Formation of the Paraná Basin, through the information from hydrocarbon exploration wells in Southeastern Brazil, where most stationary sources of carbon emissions are located. Three-dimensional (3D) implicit modeling techniques were applied not only for the volume calculation purpose, but also in the site selection stage, generating thematic 3D models of thickness, depth, structures, and distance to aquifer systems. The limestones, shales, and black shales of the Irati Formation were locally divided into six units according to geological composition and spatial continuity. The E black shale unit was considered for CO2 geological storage indicating a theoretical capacity of 1.85 Gt of CO2. The potential of the achieved capacity is promising not only for been greater than the total of CO2 locally produced but also for supporting the implantation of new projects in this region.

scholarly journals Coupled stratigraphic and U-Pb zircon age constraints on the late Paleozoic icehouse-to-greenhouse turnover in south-central Gondwana

Geology ◽  
2019 ◽  
Vol 47 (12) ◽  
pp. 1146-1150 ◽  
Author(s):  
Neil Patrick Griffis ◽  
Isabel Patricia Montañez ◽  
Roland Mundil ◽  
Jon Richey ◽  
John Isbell ◽  
...  
Keyword(s):  
Ice Age ◽  
Late Paleozoic ◽  
Karoo Basin ◽  
Base Level ◽  
South Central ◽  
Paraná Basin ◽  
Forcing Mechanisms ◽  
Sequence Boundaries ◽  
Parana Basin ◽  
Order Sequence

Abstract The demise of the Late Paleozoic Ice Age has been hypothesized as diachronous, occurring first in western South America and progressing eastward across Africa and culminating in Australia over an ∼60 m.y. period, suggesting tectonic forcing mechanisms that operate on time scales of 106 yr or longer. We test this diachronous deglaciation hypothesis for southwestern and south-central Gondwana with new single crystal U-Pb zircon chemical abrasion thermal ionizing mass spectrometry (CA-TIMS) ages from volcaniclastic deposits in the Paraná (Brazil) and Karoo (South Africa) Basins that span the terminal deglaciation through the early postglacial period. Intrabasinal stratigraphic correlations permitted by the new high-resolution radioisotope ages indicate that deglaciation across the S to SE Paraná Basin was synchronous, with glaciation constrained to the Carboniferous. Cross-basin correlation reveals two additional glacial-deglacial cycles in the Karoo Basin after the terminal deglaciation in the Paraná Basin. South African glaciations were penecontemporaneous (within U-Pb age uncertainties) with third-order sequence boundaries (i.e., inferred base-level falls) in the Paraná Basin. Synchroneity between early Permian glacial-deglacial events in southwestern to south-central Gondwana and pCO2 fluctuations suggest a primary CO2 control on ice thresholds. The occurrence of renewed glaciation in the Karoo Basin, after terminal deglaciation in the Paraná Basin, reflects the secondary influences of regional paleogeography, topography, and moisture sources.

Tectonics of the Northeastern border of the Parana Basin (Southeastern Brazil) revealed by lineament domain analysis

2019 ◽  
Vol 94 ◽  
pp. 102231 ◽  
Author(s):  
Marcos Roberto Pinheiro ◽  
Paola Cianfarra ◽  
Fernando Nadal Junqueira Villela ◽  
Francesco Salvini
Keyword(s):  
Domain Analysis ◽  
Southeastern Brazil ◽  
Paraná Basin ◽  
Parana Basin

scholarly journals Astyanax totae, a new characid species (Teleostei: Characidae) from the upper rio Iguaçu basin, southeastern Brazil

2005 ◽  
Vol 3 (3) ◽  
pp. 383-388 ◽  
Author(s):  
Carolina Ferreira Haluch ◽  
Vinícius Abilhoa
Keyword(s):  
New Species ◽  
Lateral Line ◽  
Southeastern Brazil ◽  
Caudal Fin ◽  
Dark Stripe ◽  
Fin Rays ◽  
Paraná Basin ◽  
Parana Basin ◽  
A New Species ◽  
Small Tributary

A new species of characid fish, Astyanax totae, is described from a small tributary in the upper drainage of the rio Iguaçu, Paraná basin, Brazil. The new species is distinct from most species of Astyanax by the vertically elongated humeral spot, slightly expanded above the lateral line to posterodorsal margin of opercle, followed by a midlateral dark stripe expanded from the humeral region to the median caudal-fin rays, maxilla with 2 to 5 teeth (usually 3) and 15 to 18 branched anal-fin rays.

Provenance of late Paleozoic glacial/post-glacial deposits in the eastern Chaco-Paraná Basin, Uruguay and southernmost Paraná Basin, Brazil

2020 ◽  
pp. 102989
Author(s):  
Nicholas D. Fedorchuk ◽  
Neil P. Griffis ◽  
John L. Isbell ◽  
César Goso ◽  
Eduardo L.M. Rosa ◽  
...  
Keyword(s):  
Late Paleozoic ◽  
Glacial Deposits ◽  
Paraná Basin ◽  
Parana Basin

Late Paleozoic Ice-Age rhythmites in the southernmost Paraná Basin: A sedimentological and paleoenvironmental analysis

2020 ◽  
Vol 90 (8) ◽  
pp. 969-979 ◽  
Author(s):  
Julia Tedesco ◽  
Joice Cagliari ◽  
Carolina Danielski Aquino
Keyword(s):  
Ice Age ◽  
Late Paleozoic ◽  
Interglacial Period ◽  
Fine Grained ◽  
Geochemical Proxies ◽  
Late Paleozoic Ice Age ◽  
Paraná Basin ◽  
Parana Basin

ABSTRACT Fine-grained rhythmites are a recurrent sedimentary facies in glacially influenced marine and lacustrine sequences throughout geological time. Paleoenvironmental interpretation of these ancient deposits has been a challenge, because similar rhythmites may have formed in different depositional contexts. In the Paraná Basin, the Itararé Group contains numerous successions of fine-grained rhythmites, deposited in the Carboniferous during the Late Paleozoic Ice Age (LPIA). The described rhythmites are characterized by the intercalation of fine-grained sandstones and siltstones with clay and clayey siltstones. We have identified two distinct types of rhythmites based on the contact between couplets, couplets thickness, sedimentary structures, and geochemical proxies. Type 1 rhythmites are characterized by intercalation of very fine-grained sandstone–siltstone (60–90%) with claystone (40–10%) and normal grading. Type 2 rhythmites are characterized by couplets of siltstone (50%) and claystone (50%), with a sharp contact within couplets. Type 1 rhythmites are interpreted as turbidity-current deposits, and Type 2 as distal deposits of hypopycnal flow. Geochemical proxies suggest deposition of the rhythmites under marine conditions, in a period of rising temperature and humidity, and with intensified chemical weathering. These paleoenvironmental characteristics are in agreement with the interglacial period. The preservation of thick rhythmite successions of the Itararé Group in the southern part of the basin was controlled by the constant creation of accommodation space inside paleovalleys.

A mantle flow mechanism for the late Paleozoic subsidence of the Paraná Basin

2000 ◽  
Vol 105 (B7) ◽  
pp. 16359-16370 ◽  
Author(s):  
Russell N. Pysklywec ◽  
Marcia C. L. Quintas
Keyword(s):  
Late Paleozoic ◽  
Mantle Flow ◽  
Flow Mechanism ◽  
Paraná Basin ◽  
Parana Basin
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