CARACTERIZAÇÃO MINERALÓGICA E COMPOSIÇÃO QUÍMICA DAS INCLUSÕES FLUÍDAS DE BERILO DO PEGMATITO IPÊ, MUNICÍPIO DE GOVERNADOR VALADARES. MINAS GERAIS.

The Ipê pegmatite is situated to the northwest of Minas Gerais State, Brazil, and belongs to the MarilacPegmatitic Field of the Província Pegmatítica Oriental do Brasil. The essential minerals found are: Kfeldspar,quartz, muscovite and biotite. The accessory minerals are: kaolin, albite, apatite, beryl, niobiumtantalite,garnet and tourmaline. The beryl crystals always contain abundant primary and pseudosecundaryfluid inclusions composed essentially by aqueous solutions of low salinity. Eutetic temperature data andmicro-Raman and infrared Spectroscopy analyses of the inclusions of the samples from the graphic andintermediate zones, and from the substitution body suggest that the fluids have evolved from systemswhich were originally enriched in Na+, K+, and possibly Fe2+ and Fe3+ (± CO2 ± CH4 ± N2) to Ca-richersolutions, with more abundant CO2. The fluid homogenization temperatures corroborate this evolutionhypothesis and additionally suggest that the inclusions from the graphic and intermediate zones werereequilibrated by later solutions.

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Petrogenesis and tectonic of the Urucum granitic suite, Rio Doce Valley (Minas Gerais - Brazil): an example of syn to late collisional peraluminous magmatism associated with high-angle transcurrent shear zone

Brazilian Journal of Geology ◽

10.1590/23174889201500010009 ◽

2015 ◽

Vol 45 (1) ◽

pp. 127-141 ◽

Cited By ~ 1

Author(s):

Hermínio Arias Nalini Júnior ◽

Rômulo Machado ◽

Essaid Bilal

Keyword(s):

Trace Elements ◽

Solid State ◽

Shear Zone ◽

Saturation Index ◽

Minas Gerais ◽

High Angle ◽

Accessory Minerals ◽

Major Oxides ◽

Minas Gerais State ◽

Alumina Saturation Index

The Urucum suite (582 ± 2 Ma, zircon U-Pb age), situated in the Mid-Rio Doce Valley, eastern part of Minas Gerais State, is characterized by elongated, NW-SE and N-S trending granitic massifs associated with the Conselho Peña-Resplendor high-angle shear zone. It corresponds to a syn to late collisional magmatism that presents dominant solid-state foliation. Four facies are distinguished within the Urucum suite: (i) a porphyritic (Urucum); (ii) a medium- to coarse nequigranular (Palmital); (iii) a tourmaline-bearing; and (iv) a pegmatitic facies. These facies are peraluminous, with alumina saturation index varying from 0.98 to 1.38. SiO2 contents vary from 70.7 to 73.7 wt%, with K2O values ranging from 3.5 to 5.7 wt%, Na2O from 1.9 to 4.4 wt%, MgO from 0.6 to 1.2 wt%, and CaO from 0.3 to 0.9%. Harker-type diagrams show rather continuous trends from the less-evolved Urucum facies to the more evolved tourmaline-bearing and pegmatitic facies. The behavior of several major oxides and trace elements (Fe2O3, MgO, MnO, CaO, TiO2, Al2O3, K2O, Rb and Ba) reflects the role played by fractionation of ferromagnesian minerals, feldspars and accessory minerals. Initial Sr87/Sr86 ratios vary from 0.711 to 0.716, with εNd (580 Ma) values between -7.4 to -8.2, and Sm-Nd TDM model ages ranging from 2290 to 1840 Ma.

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QUALIDADE DA ÁGUA DE IRRIGAÇÃO DE POÇOS TUBULARES E DO RIO GORUTUBA NA REGIÃO DE JANAÚBA-MG

Irriga ◽

10.15809/irriga.2005v10n4p419-426 ◽

2018 ◽

Vol 10 (4) ◽

pp. 419

Author(s):

Walder Antonio Gomes de Albuquerque Nunes ◽

João Carlos Ker ◽

Júlio César Lima Neves ◽

Hugo Alberto Ruiz ◽

Guilherme Albuquerque Freitas ◽

...

Keyword(s):

Electric Conductivity ◽

Irrigation Water ◽

Hard Water ◽

Minas Gerais ◽

Irrigation Water Quality ◽

River Waters ◽

Low Salinity ◽

Minas Gerais State ◽

Chemical Water

QUALIDADE DA ÁGUA DE IRRIGAÇÃO DE POÇOS TUBULARES E DO RIO GORUTUBA NA REGIÃO DE JANAÚBA-MG[1] Walder Antonio Gomes de Albuquerque Nunes1; João Carlos Ker2; Júlio César Lima Neves2; Hugo Alberto Ruiz2; Guilherme Albuquerque Freitas2; Raphael Moreira Beirigo21Embrapa Agropecuária Oeste, Dourados, MS. [email protected] de Solos, Universidade Federal de Viçosa, Viçosa, MG. 1 RESUMO Estudou-se a qualidade de águas provenientes de poços tubulares e do Rio Gorutuba utilizadas para irrigação de solos em 24 propriedades da região de Janaúba, Norte de Minas Gerais, cultivados com banana prata-anã. Procedeu-se à caracterização química das águas de irrigação determinando-se sua condutividade elétrica, pH, teores de Ca2+, Mg2+, Na+, K+, SiO2, CO32-, HCO3- , Cl-, além de Al, Cd, Cr, Cu, Fe, Mn, Ni, Ti e Zn.As águas de poços e do rio diferenciaram-se quimicamente, sendo que as águas de poços apresentaram maiores valores médios de condutividade elétrica e Razão de Adsorção de Sódio (RAS), assim como maiores teores de Ca2+, Mg2+, Na+, HCO3-, Cl-, Si, Mn e Zn. As águas de poços foram consideradas de médio risco de salinidade e baixo risco de sodicidade, além de estarem próximas do limiar de restrição de uso devido aos elevados teores de bicarbonato em solução. As águas do rio foram classificadas como de baixo risco de salinidade e risco severo de sodicidade. UNITERMOS: Água dura; Água de irrigação-Carbonatos. NUNES, W. A. G. A., KER, J. C., NEVES, J. C. L., RUIZ, H. A., FREITAS, G. A., BEIRIGO, R. M.; QUALITY OF IRRIGATION WATER FROM TUBULAR WELLS AND THE GORUTUBA RIVER NEAR JANAUBA-MG 2 ABSTRACT This work aimed to study the irrigation water quality from wells and from Gorutuba River used in 24 banana farms nearby Janauba, Minas Gerais State, Brazil. Chemical water characterization included electric conductivity, pH, concentrations of Ca2+, Mg2+, Na+, K+, SiO2, CO32-, HCO3- , Cl-, Al, Cd, Cr, Cu, Fe, Mn, Ni, Ti and Zn. Well and river waters differed chemically; the former presented higher electric conductivity and SAR average values, as well as higher Ca2+, Mg2+, Na+, HCO3-, Cl-, Si, Mn and Zn contents. Well waters were considered of medium salinity risk and low acidity risk and the high bicarbonate contents were close to restriction values for irrigation use. The river waters were classified as low salinity risk and severe acidity risk. KEYWORDS: hard water, Irrigation water carbonates[1] Parte da Tese de Doutoramento do primeiro autor, apresentada no Curso de Pós-Graduação em Solos e Nutrição de Plantas, Departamento de Solos, Universidade Federal de Viçosa – DPS-UFV. Trabalho financiado pela FAPEMIG.

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