Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil

Detalhes bibliográficos
Autor(a) principal: Figueiredo, Múcio do Amaral
Data de Publicação: 2006
Outros Autores: Fabris, José Domingos, Varajão, Angélica Fortes Drummond Chicarino, Couceiro, Paulo Rogério da Costa, Loutfi, Ivan Soares, Azevedo, Izabel de Souza, Garg, Vijayendra Kumar
Tipo de documento: Artigo
Idioma: por
Título da fonte: Pesquisa Agropecuária Brasileira (Online)
Texto Completo: https://seer.sct.embrapa.br/index.php/pab/article/view/7139
Resumo: The objective of this work was to characterize iron oxides from B-horizons of three soil profiles developing on gneiss of the Bação Complex geodomain in the Quadrilátero Ferrífero, Minas Gerais, Brazil. Samples were collected from the uppest, middle and lowest segments along the slope. The earth fine fractions (mean diameter, f = 2 mm) were separated for all samples. The chemical composition of the major elements was determined with the X-ray fluorescence technique; the mineralogical analysis was performed with powder X-ray diffractomer and Mössbauer spectroscopy. All samples have similar mineralogical composition, with a general occurrence corresponding to the sequence quartz >> gibbsite > kaolinite > goethite. From the 4.2 K-Mössbauer results, the coexistence of goethite (major) and hematite is confirmed. The isomorphic aluminum contents, as they were deduced from the hyperfine fields, lead to the following chemical formulas for goethites: aFe0.79Al0.21OOH (upslope), aFe0.75Al0.25OOH (midslope) and aFe0.78Al0.22OOH (downslope). The iron oxides transformation dynamics in B horizons along the slope is a useful indicator of the paleo-climatic oscillations in this area: aluminous goethite is an indicator of humid paleo-environments, whereas aluminous-poorer goethite reveals drier pedogenic conditions.
id EMBRAPA-4_aa79f1ade4dae361ab9b30eb5ebb20d7
oai_identifier_str oai:ojs.seer.sct.embrapa.br:article/7139
network_acronym_str EMBRAPA-4
network_name_str Pesquisa Agropecuária Brasileira (Online)
repository_id_str
spelling Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, BrazilÓxidos de ferro de solos formados sobre gnaisse do Complexo Bação, Quadrilátero Ferrífero, Minas Geraishematite; goethite; Mössbauer spectroscopy; aluminium substitutionhematita; goethita; espectroscopia Mössbauer; substituição de alumínioThe objective of this work was to characterize iron oxides from B-horizons of three soil profiles developing on gneiss of the Bação Complex geodomain in the Quadrilátero Ferrífero, Minas Gerais, Brazil. Samples were collected from the uppest, middle and lowest segments along the slope. The earth fine fractions (mean diameter, f = 2 mm) were separated for all samples. The chemical composition of the major elements was determined with the X-ray fluorescence technique; the mineralogical analysis was performed with powder X-ray diffractomer and Mössbauer spectroscopy. All samples have similar mineralogical composition, with a general occurrence corresponding to the sequence quartz >> gibbsite > kaolinite > goethite. From the 4.2 K-Mössbauer results, the coexistence of goethite (major) and hematite is confirmed. The isomorphic aluminum contents, as they were deduced from the hyperfine fields, lead to the following chemical formulas for goethites: aFe0.79Al0.21OOH (upslope), aFe0.75Al0.25OOH (midslope) and aFe0.78Al0.22OOH (downslope). The iron oxides transformation dynamics in B horizons along the slope is a useful indicator of the paleo-climatic oscillations in this area: aluminous goethite is an indicator of humid paleo-environments, whereas aluminous-poorer goethite reveals drier pedogenic conditions.O objetivo deste trabalho foi efetuar a caracterização mineralógica dos óxidos de ferro de horizontes B de três perfis de solos desenvolvidos sobre gnaisse do geodomínio do Complexo Bação, no Quadrilátero Ferrífero, em Minas Gerais. As amostras foram coletadas ao longo dos segmentos de alta, média e baixa vertente. As frações de terra fina (diâmetro médio, f = 2 mm) foram separadas, em todas as amostras. A composição química dos elementos maiores foi determinada por meio da técnica de fluorescência de raios X; a análise mineralógica foi realizada com difratometria de raios X e espectroscopia Mössbauer. Todas as amostras têm composição mineralógica similar, cuja ocorrência geral corresponde à seqüência quartzo >> gibbsita > caulinita > goethita. Os resultados Mössbauer a 4,2 K confirmam a coexistência de goethita (majoritária) e hematita. Os conteúdos de alumínio isomórfico foram deduzidos dos valores de campos hiperfinos e correspondem às seguintes fórmulas químicas das goethitas: aFe0,79Al0,21OOH (alta vertente), aFe0,75Al0,25OOH (meia vertente) e aFe0,78Al0,22OOH (baixa vertente). A dinâmica de transformação dos óxidos de ferro nos horizontes B ao longo da vertente é um indicador das oscilações paleoclimáticas na área: goethita mais aluminosa é um indicador do paleoambiente úmido, e goethita menos aluminosa revela condições pedogênicas mais secas.Pesquisa Agropecuaria BrasileiraPesquisa Agropecuária BrasileiraFigueiredo, Múcio do AmaralFabris, José DomingosVarajão, Angélica Fortes Drummond ChicarinoCouceiro, Paulo Rogério da CostaLoutfi, Ivan SoaresAzevedo, Izabel de SouzaGarg, Vijayendra Kumar2006-02-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://seer.sct.embrapa.br/index.php/pab/article/view/7139Pesquisa Agropecuaria Brasileira; v.41, n.2, fev. 2006; 313-321Pesquisa Agropecuária Brasileira; v.41, n.2, fev. 2006; 313-3211678-39210100-104xreponame:Pesquisa Agropecuária Brasileira (Online)instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)instacron:EMBRAPAporhttps://seer.sct.embrapa.br/index.php/pab/article/view/7139/4184info:eu-repo/semantics/openAccess2010-12-29T15:33:11Zoai:ojs.seer.sct.embrapa.br:article/7139Revistahttp://seer.sct.embrapa.br/index.php/pabPRIhttps://old.scielo.br/oai/scielo-oai.phppab@sct.embrapa.br || sct.pab@embrapa.br1678-39210100-204Xopendoar:2010-12-29T15:33:11Pesquisa Agropecuária Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa)false
dc.title.none.fl_str_mv Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
Óxidos de ferro de solos formados sobre gnaisse do Complexo Bação, Quadrilátero Ferrífero, Minas Gerais
title Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
spellingShingle Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
Figueiredo, Múcio do Amaral
hematite; goethite; Mössbauer spectroscopy; aluminium substitution
hematita; goethita; espectroscopia Mössbauer; substituição de alumínio
title_short Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
title_full Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
title_fullStr Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
title_full_unstemmed Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
title_sort Iron oxides of soils formed on gneiss of the Bação Complex geodomain, Quadrilátero Ferrífero, Minas Gerais, Brazil
author Figueiredo, Múcio do Amaral
author_facet Figueiredo, Múcio do Amaral
Fabris, José Domingos
Varajão, Angélica Fortes Drummond Chicarino
Couceiro, Paulo Rogério da Costa
Loutfi, Ivan Soares
Azevedo, Izabel de Souza
Garg, Vijayendra Kumar
author_role author
author2 Fabris, José Domingos
Varajão, Angélica Fortes Drummond Chicarino
Couceiro, Paulo Rogério da Costa
Loutfi, Ivan Soares
Azevedo, Izabel de Souza
Garg, Vijayendra Kumar
author2_role author
author
author
author
author
author
dc.contributor.none.fl_str_mv

dc.contributor.author.fl_str_mv Figueiredo, Múcio do Amaral
Fabris, José Domingos
Varajão, Angélica Fortes Drummond Chicarino
Couceiro, Paulo Rogério da Costa
Loutfi, Ivan Soares
Azevedo, Izabel de Souza
Garg, Vijayendra Kumar
dc.subject.por.fl_str_mv hematite; goethite; Mössbauer spectroscopy; aluminium substitution
hematita; goethita; espectroscopia Mössbauer; substituição de alumínio
topic hematite; goethite; Mössbauer spectroscopy; aluminium substitution
hematita; goethita; espectroscopia Mössbauer; substituição de alumínio
description The objective of this work was to characterize iron oxides from B-horizons of three soil profiles developing on gneiss of the Bação Complex geodomain in the Quadrilátero Ferrífero, Minas Gerais, Brazil. Samples were collected from the uppest, middle and lowest segments along the slope. The earth fine fractions (mean diameter, f = 2 mm) were separated for all samples. The chemical composition of the major elements was determined with the X-ray fluorescence technique; the mineralogical analysis was performed with powder X-ray diffractomer and Mössbauer spectroscopy. All samples have similar mineralogical composition, with a general occurrence corresponding to the sequence quartz >> gibbsite > kaolinite > goethite. From the 4.2 K-Mössbauer results, the coexistence of goethite (major) and hematite is confirmed. The isomorphic aluminum contents, as they were deduced from the hyperfine fields, lead to the following chemical formulas for goethites: aFe0.79Al0.21OOH (upslope), aFe0.75Al0.25OOH (midslope) and aFe0.78Al0.22OOH (downslope). The iron oxides transformation dynamics in B horizons along the slope is a useful indicator of the paleo-climatic oscillations in this area: aluminous goethite is an indicator of humid paleo-environments, whereas aluminous-poorer goethite reveals drier pedogenic conditions.
publishDate 2006
dc.date.none.fl_str_mv 2006-02-01
dc.type.none.fl_str_mv
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv https://seer.sct.embrapa.br/index.php/pab/article/view/7139
url https://seer.sct.embrapa.br/index.php/pab/article/view/7139
dc.language.iso.fl_str_mv por
language por
dc.relation.none.fl_str_mv https://seer.sct.embrapa.br/index.php/pab/article/view/7139/4184
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Pesquisa Agropecuaria Brasileira
Pesquisa Agropecuária Brasileira
publisher.none.fl_str_mv Pesquisa Agropecuaria Brasileira
Pesquisa Agropecuária Brasileira
dc.source.none.fl_str_mv Pesquisa Agropecuaria Brasileira; v.41, n.2, fev. 2006; 313-321
Pesquisa Agropecuária Brasileira; v.41, n.2, fev. 2006; 313-321
1678-3921
0100-104x
reponame:Pesquisa Agropecuária Brasileira (Online)
instname:Empresa Brasileira de Pesquisa Agropecuária (Embrapa)
instacron:EMBRAPA
instname_str Empresa Brasileira de Pesquisa Agropecuária (Embrapa)
instacron_str EMBRAPA
institution EMBRAPA
reponame_str Pesquisa Agropecuária Brasileira (Online)
collection Pesquisa Agropecuária Brasileira (Online)
repository.name.fl_str_mv Pesquisa Agropecuária Brasileira (Online) - Empresa Brasileira de Pesquisa Agropecuária (Embrapa)
repository.mail.fl_str_mv pab@sct.embrapa.br || sct.pab@embrapa.br
_version_ 1793416710584270848

Registros relacionados