Facies and depositional architecture according to a jet efflux model of a late Paleozoic tidewater grounding-line system from the Itararé Group (Paraná Basin), southern Brazil

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.

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Ichnological Research of Silurian–Devonian Strata and the Zoophycos Distribution in the Paraná Basin

Terr Plural ◽

10.5212/terraplural.v.15.2118495.033 ◽

2021 ◽

Vol 15 ◽

pp. e2118495

Author(s):

Kevin William Richter ◽

◽

Elvio Pinto Bosetti ◽

Daniel Sedorko ◽

◽

...

Keyword(s):

Depositional Environments ◽

Southern Brazil ◽

Ecological Strategies ◽

Lower Paleozoic ◽

Paraná Basin ◽

Parana Basin

The Silurian–Devonian strata of the Paraná Basin (southern Brazil) have a wide variety of ichnofossils. The first records date from the beginning of the last century, with pioneering studies in 1912 addressing the Furnas and Ponta Grossa formations. Significant advances in the ichnological knowledge of these units occurred between the 1980s and 1990s, emphasizing ichnotaxonomic characterizations. These ichnological studies were important for better understanding and describing the main depositional environments, ecological strategies, biostratigraphy, and the relation with the preserved paleofauna. In this contribution, we review this knowledge and analyze the distribution and paleoecological significance of Zoophycos, the most remarkable ichnotaxon in the Lower Paleozoic beds of the Paraná Basin.

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

Geology ◽

10.1130/g46740.1 ◽

2019 ◽

Vol 47 (12) ◽

pp. 1146-1150 ◽

Cited By ~ 18

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.

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PORE SYSTEM QUANTIFICATION AND CHARACTERIZATION IN VOLCANIC ROCKS: A CASE STUDY FROM THE LOWER CRETACEOUS SERRA GERAL GROUP, PARANÁ BASIN, SOUTHERN BRAZIL

Journal of Petroleum Geology ◽

10.1111/jpg.12735 ◽

2019 ◽

Vol 42 (3) ◽

pp. 301-317 ◽

Cited By ~ 1

Author(s):

M. Becker ◽

E. F. Lima ◽

B. L. Waichel ◽

I. F. Mantovani

Keyword(s):

Lower Cretaceous ◽

Volcanic Rocks ◽

Southern Brazil ◽

Pore System ◽

Paraná Basin ◽

Parana Basin

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

Journal of South American Earth Sciences ◽

10.1016/j.jsames.2020.102989 ◽

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

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

Journal of Sedimentary Research ◽

10.2110/jsr.2020.54 ◽

2020 ◽

Vol 90 (8) ◽

pp. 969-979 ◽

Cited By ~ 1

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.

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