Campo Belo Metamorphic Complex: Tectonic evolution of an Archean sialic crust of the southern Sao Francisco Craton in Minas Gerais (Brazil)

Citation
Ah. Oliveira et Ma. Carneiro, Campo Belo Metamorphic Complex: Tectonic evolution of an Archean sialic crust of the southern Sao Francisco Craton in Minas Gerais (Brazil), AN AC BRASI, 73(3), 2001, pp. 397-415
Citations number
46
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Multidisciplinary
Journal title
ANAIS DA ACADEMIA BRASILEIRA DE CIENCIAS
ISSN journal
0001-3765 → ACNP
Volume
73
Issue
3
Year of publication
2001
Pages
397 - 415
Database
ISI
SICI code
0001-3765(200109)73:3<397:CBMCTE>2.0.ZU;2-C
Abstract
Systematic geological studies performed in the study area allowed the chara cterization of six lithodemic units: three gneissic, one amphibolitic, one supracrustal and one fissure mafic. The mineral assemblage and the structur al record of these lithodemic units indicate that the study area was affect ed by five tectonothermal events. The structural pattern of the first and o ldest event occurred under granulite facies conditions and reveals essentia lly a sinistral kinematic pattern. The second event, showing dominant exten sional characteristics, is related to the generation of an ensialic basin f illed by the volcano-sedimentary sequence of the supracrustal lithodemic un it, The third event, which is the most expressive in the study region, is c haracterized by a vigorous regional migmatization process and by the genera tion of the Claudio Shear Zone, presenting dextral kinematic movement. The fourth event is represented by a fissure mafic magmatism (probably two diff erent mafic dike swarms) and finally, the fifth event is a regional metamor phic re-equilibration that reached the greenschist facies, closing the main processes of the tectonic evolution of the Campo Belo Metamorphic Complex.