UNIGE document Scientific Article
previous document  unige:18885  next document
add to browser collection
Title

The Mesoproterozoic Maz terrane in the Western Sierras Pampeanas, Argentina, equivalent to the Arequipa–Antofalla block of southern Peru? Implications for West Gondwana margin evolution

Authors
Casquet, C.
Pankhurst, R.J.
Rapela, C.W.
Galindo, C.
Fanning, C.M.
Baldo, E.
González-Casado, J.M.
show hidden authors show all authors [1 - 9]
Published in Gondwana Research. 2008, vol. 13, no. 2, p. 163-175
Abstract The rocks of Sierra de Maz and Sierra del Espinal (Western Sierras Pampeanas) represent pre-Famatinian (Ordovician) basement. Isotope compositions (Nd and Pb) of metasedimentary rocks and SHRIMP U–Pb dating of detrital zircons, combined with other geological evidence, show that three parallel N–S domains can be recognized. The central Maz Domain contains pre-Grenvillian metasedimentary rocks deposited between 1.2 and 1.6 Ga, that underwent Grenvillian granulite facies metamorphism and were intruded by mafic igneous rocks and massif-type anorthosites. Metasedimentary rocks have high Nd TDM ages (1.7–2.7 Ga) and very radiogenic Pb (␣=9.8–10.2), suggesting provenance from reworked early Proterozoic or Archean continental crust. The domains to the east and west of the Maz Domain consist of three metasedimentary sequences with Nd TDM ages between 1.2 and 1.6 Ga and variably radiogenic Pb (␣=9.6–10.0). U–Pb SHRIMP dating of detrital zircons, Nd TDM model ages and comparison with other data suggest that these sequences are post-Grenvillian, i.e., Neoproterozoic and/or early Paleozoic. The Maz Domain is interpreted as a suspect terrane similar to the northern Arequipa–Antofalla craton that forms the basement of the Central Andes; both underwent Grenville-age orogeny and were probably once continuous along the western margin of Amazonia (West Gondwana). © 2007 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
Keywords Sierras PampeanasU–Pb SHRIMP zircon datingNd isotopesPb isotopesGondwanaGrenville
Identifiers
Full text
Structures
Research groups Isotope Geochemistry, Geochronology and Thermochronology
Mineral Resources and Geofluids
Citation
(ISO format)
CASQUET, C. et al. The Mesoproterozoic Maz terrane in the Western Sierras Pampeanas, Argentina, equivalent to the Arequipa–Antofalla block of southern Peru? Implications for West Gondwana margin evolution. In: Gondwana Research, 2008, vol. 13, n° 2, p. 163-175. https://archive-ouverte.unige.ch/unige:18885

141 hits

0 download

Update

Deposited on : 2012-03-19

Export document
Format :
Citation style :