Cristalização Fracionada e Assimilação da Crosta Continental pelos Magmas de Rochas Alcalinas Félsicas do Estado do Rio de Janeiro

Sichel, Susanna Eleonora; Motoki, Akihisa; Iwanuch, Woldemar; Vargas, Thais; Aires, José Ribeiro; Melo, Dean Pereira de; Motoki, Kenji Freire; Balmant, Alex; Rodrigues, Juliana Gonçalves

doi:10.11137/2012_2_84_104

Cited by 5 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Mafic alkaline dyke swarms (mostly basanites and alkali basalts, plus rarer camptonites and foidites), together with subordinate felsic differentiates (tephritic phonolites, trachyandesites, trachytes and phonolites) cross-cut some alkaline complexes and the crystalline basement (e.g. Brotzu et al, 1989Brotzu et al, , 2005Sichel et al, 2012;Motoki et al, 2015).…”

Section: Introductionmentioning

confidence: 99%

TheREE-and HFSE-bearing phases in the Itatiaia alkaline complex (Brazil) and geochemical evolution of feldspar-rich felsic melts

et al. 2017

View full text Add to dashboard Cite

The Late Cretaceous Itatiaia complex is made up of nepheline syenite grading to peralkaline varieties, quartz syenite and granite, emplaced in the metamorphic rocks of the Serra do Mar, SE Brazil. The nepheline syenites are characterized by assemblages with alkali feldspar, nepheline, Fe-Ti oxides, clinopyroxene, amphibole, apatite and titanite, while the peralkaline nepheline syenites have F-disilicates (rinkite, wöhlerite, hiortdahlite, låvenite), britholite and pyrophanite as the accessory phases. The silica-oversaturated rocks have alkali feldspar, plagioclase, quartz, amphibole, clinopyroxene and Fe-Ti oxides; the chevkinite-group minerals are the featured accessory phases and are found with allanite, fluorapatite, fluorite, zircon, thorite, yttrialite, zirconolite, pyrochlore and yttrocolumbite. The major- A nd trace-element composition of the Itatiaia rocks have variations linked to the amount of accessory phases, have smooth, enriched chondritenormalized rare-earth element (REE) distribution patterns in the least-evolved nepheline syenites and convex patterns in the most-evolved nepheline syenites. The REE distribution patterns of the quartz syenites and granites show a typical pattern caused by fractional crystallization of feldspar and amphibole, in an environment characterized by relatively high oxygen fugacity (>NiNiO buffer) and high concentrations of H2O and F, supporting the crystallization of hydrous phases, fluorite and F-disilicates. The removal of small amounts of titanite in the transition from the least-evolved to the most-evolved nepheline syenites stems from petrogenetic models involving REE, and is shown to be a common feature of the magmatic evolution of many other syenitic/trachytic/phonolitic complexes of the Serra do Mar and elsewhere

show abstract

Section: Introductionmentioning

confidence: 99%

TheREE-and HFSE-bearing phases in the Itatiaia alkaline complex (Brazil) and geochemical evolution of feldspar-rich felsic melts

et al. 2017

View full text Add to dashboard Cite

show abstract

“…First, the slow K solubility from this type of rock considering the short term that the experiment was conducted (SICHEL et al, 2012). The second possible explanations refers to the need of using a more finely grounded phonolite, preferably with particle size < 0.002 mm, that would accelerate K solubility (THEODORO; LENARDOS, 2006).…”

Section: Resultsmentioning

confidence: 99%

Microtopographies and soil conditioners on growth and nutrition of </i>Eucalyptus saligna</i> in abandoned agricultural field

Schoen

Aumond²,

Stürmer³

2022

Ciênc. Florest.

View full text Add to dashboard Cite

Rehabilitation of abandoned agricultural fields is a multidisciplinary task, in pursuit of the development of sustainable productive systems. The objective of this study was to evaluate the effect of microtopography technique and soil conditioners on survival, growth and nutrition of Eucalyptus saligna of an abandoned agriculture field. Plots of microtopography and flat plots were established in an abandoned agriculture field (27º 12.08' S and 49º 07.60' W). Within plots, we stablished subplots with plants, which received the application of soil conditioners, including phonolite (100 g), mycorrhizal inoculant (200 cm3), pulp sludge and carbonized rice husk (200 cm3), phonolite (100 g) and mycorrhizal inoculant (200 cm3) and control. The experiment monitoring occurred between november 2013 to october 2014 and growth parameters were measured after 30, 90, 150, 210, 270 and 330 days of the experiment onset. From each plant, height, stem diameter and canopy area were measured. At the end of the experiment, 50 leaves were collected from each plant to determine potassium and phosphorus concentrations. The native mycorrhizal community was characterized by bioassay and species identification of field-collected spores. Survival rates of Eucalyptus saligna tended to be higher in microtopography plots. The Plant height, stem diameter, canopy area, and shoot P and K concentration were significantly higher in plants at microtopography plots. Soil conditioners influenced significantly the shoot K concentration. The application of microtopography technique improved survival, growth, and nutrition of Eucalyptus saligna, and it represents an important strategy to rehabilitate abandoned agricultural fields.

show abstract

“…Estes todos são intrudidos por diques máficos do Eocretáceo (Motoki et al, 2009b;Figura 5A). Os complexos de rochas alcalinas félsicas do Cretáceo ao Eocenozoico (Figura 5D; Sichel et al, 2012), tais como Itatiaia (Brotzu et al, 1997); Morro Redondo (Brotzu et al, 1989); Serra dos Tomazes (Ferrari et al, 1977); Tinguá (Derby, 1897); Mendanha (Motoki et al, 2007a); Itaúna (Motoki et al, 2008b); Tanguá; Rio Bonito; Soarinho ; Morro dos Gatos (Motoki et al, 2012c); Morro de São João (Brotzu et al, 2007); Ilha de Cabo Frio , são intrusivos nas todas as unidades acima citadas. Uma parte destes acompanham condutos subvulcanicos (e.g.…”

Section: Geologia Regionalunclassified

Análises Geomorfológicas do Platô de Teresópolis e da Serra do Mar, RJ,com o Auxílio de Seppômen e ASTER GDEM e sua Relação aos Tectonismos Cenozoicos

Aires

Motoki²,

Motoki

et al. 2013

Anuário IGEO-UFRJ

Self Cite

View full text Add to dashboard Cite

ResumoEste trabalho apresenta análises geomorfológicas do Platô de Teresópolis, a escarpa da Serra do Mar e as áreas adjacentes, RJ, com o auxílio da técnica de seppômen e os dados topográficos de satélite ASTER GDEM e, sua relação ao tectonismo cenozoico. De acordo com o mapa de seppômen da grade de 4 km, a área estudada é dividida em três domínios geomorfológicos, a Baixada Fluminense (RJL), a escarpa da Serra do Mar (SMS) e o Platô de Teresópolis (TRH). A Baixada Fluminense, que corresponde à área do Graben de Guanabara, é constituída pelas planícies de depósitos aluvionares e as áreas de morros baixos que expõem o embasamento metamórfico. Os limites entre essas são bruscos e lineares, sugerindo existência de falhas e grabens pequenos. Os topos destes morros estão quase na mesma altitude, constituindo uma superfície de seppômen com altitude aproximada de 100 m. Os mapas de seppômen das grades de 4 km e 2 km apresentam que o topo da escarpa da Serra do Mar tem altitude aproximada de 1300 m e, portanto esta falha norma tem desnível de 1200 m. A escarpa tem direção de N75°E e é dividida em segmentos de 15 km a 30 km de comprimento. Em certas localidades da escarpa, observa-se a morfologia de megadeslizamento. O Platô de Teresópolis é inclinado à N30°W com a declividade média de 0.9°. Os sistemas de drenagens no platô apresentam três orientações, N60°E, N10°E e N75°W. Ao longo do Rio Paraíba do Sul, ocorre uma depressão morfológica linear com 20 km de largura e profundidade relativa de 300 m, sugerindo presença de um graben raso. Sobre o Platô de Teresópolis, ocorrem três alinhamentos de saliências morfológicas orientados em N50°E, com altura relativa máxima de 900 m. Os histogramas de distribuição altimétrica para as superfícies de seppômen sugerem que essas são inselbergs remanescentes antes do movimento da falha da escarpa do Serra do Mar. As falhas normais e os sistemas de fraturas do Cenozoico desta área são frequentemente discordantes com a estrutura do embasamento. Este fenômeno é explicado pelo modelo de reativação das estruturas do manto litosférico, e não, da crosta continental. Palavras-chave: Platô de Teresópolis; Serra do Mar; seppômen; GDEM; BAZ; tectonismo Cenozoico Abstract This paper presents geomorphological analyses of the Teresópolis Plateau, the Serra do Mar Cliff, and the adjacent areas, State of Rio de Janeiro, Brazil, with the help of summit level technique using ASTER GDEM satellite topographic data, and its relation to the Cenozoic tectonism. According to the summit level map of the grid of 4 km, the studied area is divided into three geomorphologic domains, Rio de Janeiro Lowland (RJL), Serra do Mar Scarp (SMS), and Teresópolis Highland (TRH). The Rio de Janeiro Lowland, which corresponds to the Guanabara Graben area, is constituted by alluvial deposit planes and the areas of low hills that expose the metamorphic basement. Their limits are sharp and linear suggesting existence of small faults and grabens. The tops of the low hills are almost at the same altitude, constituting a summit l...

show abstract

Cristalização Fracionada e Assimilação da Crosta Continental pelos Magmas de Rochas Alcalinas Félsicas do Estado do Rio de Janeiro

Cited by 5 publications

References 0 publications

TheREE-and HFSE-bearing phases in the Itatiaia alkaline complex (Brazil) and geochemical evolution of feldspar-rich felsic melts

TheREE-and HFSE-bearing phases in the Itatiaia alkaline complex (Brazil) and geochemical evolution of feldspar-rich felsic melts

Microtopographies and soil conditioners on growth and nutrition of </i>Eucalyptus saligna</i> in abandoned agricultural field

Análises Geomorfológicas do Platô de Teresópolis e da Serra do Mar, RJ,com o Auxílio de Seppômen e ASTER GDEM e sua Relação aos Tectonismos Cenozoicos

Contact Info

Product

Resources

About