Pre-orogenic connection of the foreland domains of the Kaoko–Dom Feliciano–Gariep orogenic system
•Detrital zircon analysis of Neoproterozoic Dom Feliciano Belt supracrustal rocks.•Minimum age constraint for sedimentation into Brusque Complex rift basin at ca. 810 Ma.•Mesoproterozoic zircon age fractions reveal major African sedimentary protosources.•Brusque Complex detrital zircon record correl...
Saved in:
Published in | Precambrian research Vol. 354; p. 106060 |
---|---|
Main Authors | , , , , , , |
Format | Journal Article |
Language | English |
Published |
Elsevier B.V
01.03.2021
Elsevier |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | •Detrital zircon analysis of Neoproterozoic Dom Feliciano Belt supracrustal rocks.•Minimum age constraint for sedimentation into Brusque Complex rift basin at ca. 810 Ma.•Mesoproterozoic zircon age fractions reveal major African sedimentary protosources.•Brusque Complex detrital zircon record correlates with Kaoko Belt and Porongos Complex.•Data show close proximity between the Luis Alves and Congo cratons at Rodinia breakup.
Neoproterozoic metasedimentary rocks in the foreland domains of the Kaoko–Dom Feliciano–Gariep orogenic system record sedimentation from the breakup of Rodinia to the amalgamation of Gondwana, and thus provide ideal subjects for investigation of the mutual pre-orogenic positions of rifted margins of the African and South American cratonic blocks. U–Pb isotopic dating of zircon in the Brusque Complex of the northern Dom Feliciano Belt, Brazil, provides new constraints on the timing and sources of Neoproterozoic sedimentation along the eastern margin of the Luis Alves Craton. The minimum age of sedimentation is constrained by a U–Pb zircon age of 811 ± 6 Ma from a dyke cross-cutting the Brusque Complex. U–Pb detrital zircon analysis reveals two distinct groups: one with ages ca. 2.2–2.0 Ga consistent with erosion of the adjacent Luis Alves Craton, and another with ages ca. 2.1–1.8 and 1.6–1.0 Ga consistent with erosion of Paleoproterozoic to Mesoproterozoic igneous provinces and/or supracrustal sequences at the edge of the Congo Craton. The age distributions match with analogous rocks of the central Dom Feliciano Belt and the Kaoko Belt, and show similarities with the Gariep Belt, suggesting deposition in a system of coeval and spatially related paleobasins around the time of Rodinia breakup. The absence of Neoproterozoic detrital zircon close to the age of sedimentation suggests deposition in an intracontinental rift or passive margin. A third group contains a significant proportion of Neoproterozoic ca. 670–560 Ma zircon, suggesting similarities with the adjacent Itajaí Basin syn-orogenic foreland sedimentary rocks. This indicates that foreland basin sediments were partly tectonically interleaved with the pre-orogenic metasediments of the Brusque Complex during late-stage orogenic deformation. The findings support an intracontinental rifting model for the formation of the Kaoko–Dom Feliciano–Gariep basin system. The data further indicate that the Luis Alves Craton was in close proximity to the Congo Craton, and likely with the Nico Pérez Terrane and the Kalahari Craton, at the onset of Tonian rifting and the breakup of Rodinia. |
---|---|
Bibliography: | Percival, J.J. (2022). Neoproterozoic orogenesis in south-eastern South America - An examination of pre-orogenic rifting, sedimentation, and mountain building processes recorded in the Dom Feliciano Belt. (Doctoral thesis). <a href=https://hdl.handle.net/10037/23705>https://hdl.handle.net/10037/23705 |
ISSN: | 0301-9268 1872-7433 1872-7433 |
DOI: | 10.1016/j.precamres.2020.106060 |