摘要：Magmatic evolution of Serrinha suite, southernmost portion of São Francisco Craton, Minas
Gerais State, Brazil.
The Serrinha suite outcrops at the southernmost portion of São Francisco Craton and comprises the
Brito quartz-diorite, Brumado de Cima granodiorite, Brumado de Baixo granodiorite, two granophyres
and two sub-volcanic – volcanic felsic bodies. The Serrinha suite intrudes metaultramafic, metamafic
and metasedimentary rocks of the Nazareno greenstone belt and have amphibolite and quartzite xenoliths
of the greenstone. The petrographic similarities of the bodies of the Serrinha suite suggest a same
parental magma but the textural diversities point to different crystallization conditions due to the lost of
volatiles and cooling of the magma in the various depth levels. In the bodies of the ‘granitic’ texture,
volatile elements escape slowly from the magma, nucleation rate and velocity of growth of the crystals
were high, while in the sub-volcanic – volcanic rocks volatile elements escape fast, the nucleation rate
and the velocity of growth of the crystals were short. The interval age of the sub-volcanic – volcanic
rocks (2220 ± 3 Ma – 1,8 Ga) correspond to a new felsic magmatic pulse of southernmost portion of the
São Francisco craton.
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