Abstract
Zircon U-Pb geochronology was applied to investigate the provenance, depositional ages, and paleogeography of the southwestern Gondwana in detrital and ash fall sediments from Carboniferous to Jurassic succession of the southern Paraná Basin. Four detrital age populations suggest provenance from local and distal sources located to the south, southeast, and southwest: (i) Archean to Paleoproterozoic zircons from the Rio de La Plata Craton, Nico Peres and Taquarembó terranes; (ii) Grenvillian zircons from the basement of the Gondwanides and Namaqua–Natal belts; (iii) Neoproterozoic grains from the Don Feliciano Belt; and (iv) Phanerozoic populations from Paleozoic orogenic belts and related foreland systems in Argentina, as well as eroded units of the Paraná Basin. The paleogeographic reconstruction indicates an evolution in three distinct stages: (1) a gulf open to the Panthalassa Ocean during the Carboniferous; (2) an epicontinental sea with the rise of the Gondwanides Orogeny during the Permian; and (3) continental deposits controlled by an intra-plate graben system during the Triassic. Permian–Triassic volcanogenic zircons provide constrained maximum depositional ages and attested persistent volcanism, related to the Choiyoi magmatism and effects of the climate change episodes. During the Triassic, the extensional graben system recorded the uplift of the basement through regional northwest and northeast fault systems, and the recycling of Permian zircons, modifying source-to-sink relationships.
Original language | English |
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Article number | 225 |
Number of pages | 36 |
Journal | Geosciences (Switzerland) |
Volume | 13 |
Issue number | 8 |
DOIs | |
Publication status | Published - Aug 2023 |
Bibliographical note
Funding Information:The authors thank the editors of this volume (Andrew Morton, Shane Tyrel, and Gustavo Zvirtes) and the reviewers for the criticism and improvement of the discussions. Ruy P. Philipp express their gratitude for the research grant from the Brazilian National Council for Scientific and Technological Development (CNPq). We also thank the Geochronological Research Center (CPGEO) of the Geosciences Institute of the São Paulo University for its co-operation and for facilitating the U-Pb zircon analyses.
Keywords
- ash fall layers
- gondwana
- gondwanides belt
- maximum depositional ages
- paleogeography
- paraná basin
- provenance
- zircon geochronology