Zircon U–Pb age constraints on the Paleoproterozoic sedimentary basement of the Ediacaran Porongos Group, Sul-Riograndense Shield, southern Brazil. (November 2015)

• Record Type: Journal Article
• Authors: Pertille, Juliana; Hartmann, Léo Afraneo; Philipp, Ruy Paulo
• Is Part Of: Journal of South American earth sciences. Volume 63(2015:Nov.)
• Page Start: 334
• Page End: 345
• Publication Date: 2015-11
• Subjects: Zircon -- U–Pb data -- Provenance -- Paleoproterozoic basement -- Porongos Group; Geology -- Latin America -- Periodicals; Earth sciences -- Latin America -- Periodicals; Geology -- Antarctica -- Periodicals; Earth sciences -- Antarctica -- Periodicals; Geology -- Caribbean Area -- Periodicals; Earth sciences -- Caribbean Area -- Periodicals; Géologie -- Amérique latine -- Périodiques; Sciences de la terre -- Amérique latine -- Périodiques; Géologie -- Antarctique -- Périodiques; Sciences de la terre -- Antarctique -- Périodiques; Géologie -- Caraïbes (Région) -- Périodiques; Sciences de la terre -- Caraïbes (Région) -- Périodiques; Earth sciences; Geology; Antarctica; Caribbean Area; Latin America; Periodicals; 550.5
• DOI: 10.1016/j.jsames.2015.08.005
• Languages: English
• ISSNs: 0895-9811

Abstract

Abstract: Thick quartzites record significant information on cratonic environments during long geological periods. The capacity to resist weathering and deformation turn the quartzite covers especially useful in the provenance studies of Precambrian basins. Provenance of 194 detrital zircon grains from two samples of thick quartzite cover on the Paleoproterozoic Encantadas Complex displays mostly Paleoproterozoic (95%) and minor Archean (5%) sources. The results indicate that sediments were derived from the La Plata Craton with the maximum depositional age at 2.03 Ga possibly up to 1.7 Ga. In comparison, the adjacent Porongos Group has provenance data of 61 detrital zircon grains indicating mostly Mesoproterozoic (69%), subordinately Paleoproterozoic (26%) and minor Archean ages (5%). Considering previous published data, the Porongos Group is Ediacaran in age and probably chronocorrelated with sedimentary basins from the Tandilia Belt (Argentina). Therefore, the quartzite cover and the Porongos Group require distinct evolution in time and in tectonic environment. Graphical abstract: Highlights: The maximum depositional age of the Santana Formation is 2.03 Ga possibly up to 1.7 Ga. The Porongos Group had Paleoproterozoic to Neoproterozoic sources. The tectonic evolution of the quartzite cover and the Porongos Group was distinct in time and environment.