All Title Author
Keywords Abstract

Publish in OALib Journal
ISSN: 2333-9721
APC: Only $99


Relative Articles

U-Pb Geochronology of the Jebba Granitic Gneiss and Its Implications for the Paleoproterozoic Evolution of Jebba Area, Southwestern Nigeria

The Glória quartz-monzodiorite: isotopic and chemical evidence of arc-related magmatism in the central part of the Paleoproterozoic Mineiro belt, Minas Gerais State, Brazil

The Glória quartz-monzodiorite: isotopic and chemical evidence of arc-related magmatism in the central part of the Paleoproterozoic Mineiro belt, Minas Gerais State, Brazil

Paleoproterozoic granitic magmatism in the Lüliang area, North China Craton:constraint from isotopic geochronology

Ocorrência de rochas da fácies granulito no Cintur?o Mineiro, Minas Gerais, Brasil

Late-Paleoproterozoic granite events and their geological significance in Helanshan area, Inner Mongolia: Evidence from geochronology
内蒙古贺兰山地区古元古代晚期的花岗岩浆事件及其地质意义: 同位素年代学的证据

Middle Paleoproterozoic crustal extensional regime in the North China Craton: New evidence from SHRIMP zircon U-Pb dating and whole-rock geochemistry of meta-gabbro in the Anshan-Gongchangling area
华北克拉通古元古代中期伸展体制新证据:鞍山-弓长岭地区变质辉长岩的锆石SHRIM PU-Pb定年和全岩地球化学


Protolith age of Santa Maria Chico granulites dated on zircons from an associated amphibolite-facies granodiorite in southernmost Brazil

SHRIMP U-Pb zircon dating for Qiashikansayi granodiorite, the northern Altyn Tagh mountains and its geological implications


Nd-Sr Isotopic Geochemistry and U-Pb Geochronology of the Fé Granitic Gneiss and Lajedo Granodiorite: Implications for Paleoproterozoic Evolution of the Mineiro Belt, Southern S o Francisco Craton, Brazil

Keywords: Fé granitic gneiss , Lajedo granodiorite , U-Pb geochronology , Isotopic geochemistry , Mineiro belt , Tectonics

Full-Text   Cite this paper   Add to My Lib


The Fé granitic gneiss and Lajedo granodiorite belong to a voluminous felsic-mafic plutonism, tectonically linked toPaleoproterozoic magmatic evolution of the Mineiro Belt, southern portion of the S o Francisco Craton, central-easternBrazil. The Fé pluton is located north of the Lenheiros shear zone and is intrusive with respect to the Rio das Mortesgreenstone belt and pyroxenite - gabbroic bodies, as indicated by xenoliths of gneiss and amphibolite, in the first case, andpyroxenite in the latter. The Lajedo granodiorite is located south of the Lenheiros shear zone and cuts the metamafic rocks ofthe Forro peridotite – pyroxenite and mafic and intermediate rocks of the Nazareno greenstone belt, as evidenced by xenolithsfrom the latter unit. The modal composition of the Fé granitic gneiss lies within the ranges of monzogranite and syenogranite.It is peraluminous and shows a large variation in K2O content, which implies a middle-K calc-alkaline to high-K calc-alkalinetendency. The Lajedo modal composition is consistent with granodioritic and tonalitic compositions. It indicates a predominantlyperaluminous composition and calc-alkaline character. The U-Pb zircon crystallization age of the Fé granitic gneiss is 2191± 9 Ma, whereas the Lajedo granodiorite yields 2208 ± 26 Ma. The Nd/Sr characteristics of the Fé and Lajedo plutons areconsistent with mixtures of enriched mantle (EMI-type), DMM and crustal components during magma genesis in a plutonicarc setting, while the low 87Sr/86Sri ratios point to contribution of mafic rock protoliths during magma genesis. This is also inaccordance with the characteristic xenoliths observed within the investigated plutons from the Nazareno and Rio das Mortesgreenstone belts. The Fé granitic gneiss and Lajedo granodiorite show tectonic characteristics which are comparable to thoseof nearby coeval plutons: Brito quartz-diorite (2221 ± 2 Ma), Brumado de Cima granodiorite (2219 ± 2 Ma), Brumado deBaixo granodiorite (2218 ± 3 Ma), Gloria quartz-monzodiorite (2188 ± 29 Ma), Cassiterita Trondhjemite/Tonalite (2162± 10 Ma), Rio Grande diorite (2155 ± 3 Ma), Brumado diorite (2131 ± 4 Ma) and Ritápolis granite (2121 ± 7 Ma). As a whole,the integrated data and geologic setting of the plutons in the Mineiro belt define a well-constrained pre- to syntectonic phaseof the Mineiro Belt to the period between 2221 and 2121 Ma.


comments powered by Disqus

Contact Us


微信:OALib Journal