RT Journal Article
T1 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
A1 Casquet, César
A1 Pankhurst, R.J.
A1 Rapela, Carlos W.
A1 Galindo Francisco, Mª del Carmen
A1 Fanning, C.M.
A1 Chiaradia, Massimo
A1 Baldo, Edgardo G.
A1 González Casado, José Manuel
A1 Dahlquist, Juan A.
AB The rocks of Sierra de Maz and Sierra del Espinal (Western Sierras Pampeanas) represent pre-Famatinian (Ordovician) basement. Isotopecompositions (Nd and Pb) of metasedimentary rocks and SHRIMP U–Pb dating of detrital zircons, combined with other geologicalevidence, show that three parallel N–S domains can be recognized. The central Maz Domain contains pre-Grenvillian metasedimentaryrocks deposited between 1.2 and 1.6 Ga, that underwent Grenvillian granulite facies metamorphism and were intruded by mafic igneousrocks and massif-type anorthosites. Metasedimentary rocks have high Nd TDM ages (1.7–2.7 Ga) and very radiogenic Pb (μ=9.8–10.2),suggesting provenance from reworked early Proterozoic or Archean continental crust. The domains to the east and west of the Maz Domainconsist of three metasedimentary sequences with Nd TDM ages between 1.2 and 1.6 Ga and variably radiogenic Pb (μ=9.6–10.0). U–PbSHRIMP 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 CentralAndes; both underwent Grenville-age orogeny and were probably once continuous along the western margin of Amazonia (West Gondwana).
PB Elsevier Science B. V., Amsterdam
SN 1342-937X
YR 2008
FD 2008
LK https://hdl.handle.net/20.500.14352/49523
UL https://hdl.handle.net/20.500.14352/49523
LA eng
DS Docta Complutense
RD 1 may 2024