St Andrews Research Repository

St Andrews University Home
View Item 
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  •   St Andrews Research Repository
  • University of St Andrews Research
  • University of St Andrews Research
  • University of St Andrews Research
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

A Paleoproterozoic intra-arc basin associated with a juvenile source in the Southern Brasilia Orogen : application of U-Pb and Hf-Nd isotopic analyses to provenance studies of complex areas

Thumbnail
View/Open
Hawkesworth_Paleoproterozoic_PR_AM.pdf (1.158Mb)
Date
05/2016
Author
Westin, Alice
Neto, Mario C. Campos
Hawkesworth, Chris
Cawood, Peter Anthony
Dhuime, Bruno
Delavault, Hélène
Funder
NERC
Grant ID
NE/J021822/1
Keywords
U-Pb LA-MC-ICP-MS
Lu-Hf LA-MC-ICP-MS
Nd isotopes
Provenance
Tectonic setting
Continental crust generation
QE Geology
DAS
Metadata
Show full item record
Altmetrics Handle Statistics
Altmetrics DOI Statistics
Abstract
Early Proterozoic sedimentary basins are an important record of crust generation processes and consequently a fundamental key to unravelling Earth's evolution through geological time. Sediments within the basins are typically deformed and metamorphosed by subsequent tectonothermal events, which can obliterate their links to source terranes. Nd-whole-rock and detrital zircon U-Pb and Lu-Hf isotopic analyses are among the most reliable tools to be used in provenance investigations, since zircon is a resilient mineral and the Sm-Nd system is not extensively modified during metamorphism. These methods have been applied to a study of the provenance and tectonic setting of the São Vicente Complex, preserved in a Neoproterozoic passive margin related allochthon within the Southern Brasilia Orogen. The complex consists of siliciclastic and calc-silicate gneisses with mafic and minor ultramafic rocks, which were deformed and metamorphosed during late Neoproterozoic collision between the Paranapanema Block and the São Francisco-Congo plate. Detrital zircons indicate derivation from a juvenile Paleoproterozoic source terrane (peaks of crystallisation ages of ca. 2130 Ma, 2140 Ma and 2170 Ma; ɛHft between +0.1 and +6.0; NdTDM = 2.31-2.21 Ga; ɛNdt = +1.6 to +2.8), with a minor contribution from older continental crust. Interlayered amphibolite rocks, with juvenile signatures (ɛHft = +5.8 to +8.2; NdTDM = 2.14 and 2.30 Ga; ɛNdt = +2.2 and +3.2), yielded similar ages of 2136 ± 17 and 2143 ± 14 Ma, suggesting syn-sedimentary magmatism. Thus, the maximum age of deposition at around 2130 Ma represents the best estimate of the depositional age of the complex. The dominance of detrital zircons ages close to the age of deposition, along with syn-sedimentary magmatism, imply a convergent margin basin tectonic environment for the São Vicente Complex, with similarities to fore arc basin and trench deposits. Amphibolite and meta-sedimentary rocks point to important juvenile magmatism around 2.14 Ga. Juvenile Rhyacian (ca. 2.1 Ga) granite-granodiorite-tonalite orthogneisses with arc-related geochemical signatures (Pouso Alegre Complex) that override the São Vicente Complex, are the probable main source of detritus within the complex. Both basin and source were part of the southern edge of the São Francisco plate during the assembly of West Gondwana, and served as sources for early Neoproterozoic passive margin related basins. The age of intrusive anorogenic A-type Taguar granite indicates that by 1.7 Ga the São Vicente Complex was in a stable tectonic environment.
Citation
Westin , A , Neto , M C C , Hawkesworth , C , Cawood , P A , Dhuime , B & Delavault , H 2016 , ' A Paleoproterozoic intra-arc basin associated with a juvenile source in the Southern Brasilia Orogen : application of U-Pb and Hf-Nd isotopic analyses to provenance studies of complex areas ' , Precambrian Research , vol. 276 , pp. 178-193 . https://doi.org/10.1016/j.precamres.2016.02.004
Publication
Precambrian Research
Status
Peer reviewed
DOI
https://doi.org/10.1016/j.precamres.2016.02.004
ISSN
0301-9268
Type
Journal article
Rights
Copyright © 2016 Published by Elsevier B.V. This work is made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://dx.doi.org/10.1016/j.precamres.2016.02.004
Description
A. Westin and M.C. Campos Neto acknowledge support from São Paulo Research Foundation (FAPESP) through grants 2011/13311-9, 2013/13530-8 and 2013/19095-1. A. Westin is a grant holder at FAPESP and M. C. Campos Neto is a CNPq researcher. P. A. Cawood, C. J. Hawkesworth and H. Delavault acknowledge support from Natural Environment Research Council grant NE/J021822/1.
Collections
  • University of St Andrews Research
URL
http://www.sciencedirect.com/science/article/pii/S0301926816000668#appd002
URI
http://hdl.handle.net/10023/10330

Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

Advanced Search

Browse

All of RepositoryCommunities & CollectionsBy Issue DateNamesTitlesSubjectsClassificationTypeFunderThis CollectionBy Issue DateNamesTitlesSubjectsClassificationTypeFunder

My Account

Login

Open Access

To find out how you can benefit from open access to research, see our library web pages and Open Access blog. For open access help contact: openaccess@st-andrews.ac.uk.

Accessibility

Read our Accessibility statement.

How to submit research papers

The full text of research papers can be submitted to the repository via Pure, the University's research information system. For help see our guide: How to deposit in Pure.

Electronic thesis deposit

Help with deposit.

Repository help

For repository help contact: Digital-Repository@st-andrews.ac.uk.

Give Feedback

Cookie policy

This site may use cookies. Please see Terms and Conditions.

Usage statistics

COUNTER-compliant statistics on downloads from the repository are available from the IRUS-UK Service. Contact us for information.

© University of St Andrews Library

University of St Andrews is a charity registered in Scotland, No SC013532.

  • Facebook
  • Twitter