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| Sobrinho,José M. Azevedo; Janas,Valdecir A.; Simonetti,Antonio; Heaman,Larry M.; santoro,Jair; Diniz,Hélio N.. |
| The Ilha Anchieta Quartz Monzonite (IAQM) occupies most of the homonymous island in the coast of the state of São Paulo, and is intrusive into foliated rocks of the ~565 Ma Ubatuba Charnockite. The main petrographic variety is a porphyritic biotite-hornblende quartz monzonite with 2-4 cm tabular microcline megacrysts set in a medium-grained groundmass and magmatic foliation. Outcrop-scale structures indicate cumulative processes (modal and grain-size magmatic banding) and interaction with basic magmas (mafic microgranular enclaves). Lithogeochemical data indicates that the main variety is intermediate to acid (S1O2 = 63-67%), alkali-calcic, metaluminous and magnesian (mg# ~30), showing moderate Sr (300-400 ppm) and Ba (~1500 ppm) contents and relatively... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Granite; Lithogeochemistry; LA-ICPMS; Zircon U-Pb dating; Ribeira Belt. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652011000300010 |
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