
Geocronologia e geologia isotópica dos terrenos pré-cambrianos da porção sul-oriental do Estado de São Paulo
2004; UNIVERSIDADE DE SÃO PAULO; Volume: 4; Issue: 1 Linguagem: Inglês
10.5327/s1519-874x2004000100004
ISSN2316-9095
AutoresCláudia Regina Passarelli, Miguel Ângelo Stipp Basei, Mário da Costa Campos Neto, Oswaldo Siga Júnior, Hélcio José dos Prazeres Filho,
Tópico(s)Geological and Geochemical Analysis
ResumoIn the southeastern region of São Paulo State four major tectonic domains were defined. The Embu Domain, north of the Cubatão Shear Zone (CSZ), is composed of metasedimentary rocks, and peraluminous granites (ca. 600 Ma), whose intrusion was controlled by E-NE shear zones, and which have model Nd Tdm age around 2.0 Ga. Gneiss-migmatite rocks (612 Ma) and related granites (580 Ma) predominate in the Mongaguá Domain, which is limited by the Cubatão and Itariri shear zones. These rocks have different model Nd Tdm ages between 1.7 and 2.2 Ga. The Registro Domain, between Cubatão - Itariri Shear System (CISS) and the Serrinha Shear Zone (SSZ), is formed by metasediments and granitic rocks with migmatitic features, and represents a paleoproterozoic domain (1.9 - 2.2 Ga) intensely affected in Neoproterozoic times (750 - 580 Ma). Rocks of the Iguape Domain, limited to the north by the SSZ, include granites (ca. 600 Ma) and low grade metasediments. It is probable that all these tectonic blocks were juxtaposed during a short time interval at the end of Neoproterozoic. The joining of the Registro to the Embu Domain occurred at about 596 Ma along an E-W shear zone. The 598 Ma peraluminous granites of the Embu Domain may register the arrival of the Mongaguá Domain against the newly formed Registro-Embu Domain. The welding of the Iguape and Registro domains probably occurred at 575 Ma, as suggested by the U-Pb (monazite) age of the protomylonitic granites of the SSZ.
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