QUÍMICA MINERAL E IDADES U-Pb DE MONAZITAS DE PLACERS MARINHOSDA REGIÃO NORTE FLUMINENSE

Este trabalho abrange o estudo de química mineral e geocronologia U-Pb de grãos de monazita, composicionalmentehomogêneos, provenientes de várias jazidas explotadas pelas Indústrias Nucleares do Brasil (INB) em placers marinhos da região de Buena,litoral norte fluminense. A área está localizada na região da Bacia de Campos e, geologicamente, pertence à Província TectônicaMantiqueira, que representa um sistema orogênico neoproterozóico desenvolvido na borda sudeste do Cráton São Francisco. As idades UPbobtidas por LA-ICP-MS abrangem um intervalo entre 486 Ma e 579 Ma, sendo que as idades mais jovens são de grãos de monazitas ricosem cério. Por outro lado, as idades mais antigas correspondem a grãos de monazitas com tendência à composição cheralítica, nos quaisocorre um enriquecimento principalmente em CaO e ThO2. A comparação dessas idades com informações geológicas regionais permiteinferir as suítes G2 (granitos granada-biotita gnaisse foliado) e G3 (leucogranitos, não deformados, encaixados em G2) como rochas-fonteda população de monazita mais antiga, suítes estas relacionadas com o arco sin-colisional desenvolvido simultaneamente aometamorfismo e à deformação regional Neoproterozóica. Já a população de monazita mais jovem pode ser proveniente de corposgraníticos das suítes G4 (plútons magmáticos zonados) e G5 (ballons magmáticos), representantes das fases pós-colisionais.Palavras-chave: Monazita, quimica mineral, idades U-Pb, LA-ICP-MS. ABSTRACTMINERAL CHEMISTRY AND U-Pb AGES OF MONAZITE FROM MARINE PLACERS OF THE NORTHERN RIO DE JANEIRO STATE - Thisresearch focusses on mineral chemistry and U-Pb geochronology of monazite grains of homogeneous composition, originating from severalmarine-placer deposits exploited by Indústrias Nucleares do Brasil (INB), in Buena, northern Rio de Janeiro State. Buena is located close tothe Campos Basin and related to the geological context of the Mantiqueira Tectonic Province, which represents a neoproterozoic orogenicsystem developed in the southern edge of the São Francisco Craton. Uranium-Pb ages by LA-ICP-MS fall between 486 Ma and 579 Ma.Younger ages are related to Ce-rich monazite. Older ages correspond to monazite with cheralitic signature, chiefly enriched in CaO andThO2. These ages are interpreted in the geological context of the Mantiqueira Tectonic Province as rock sources for older monazites, whichare correlated to syn-collisional arc simultaneously developed together the neoproterozoic regional metamorphism and deformation. Theyounger monazites came from granitic plutons of G4 and G5 suites, related to post-collisional phases.Keywords: Monazite, mineral chemistry, U-Pb ages, LA-ICP-MS.

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K-Ar AND Rb-Sr DATING OF NANOMETER-SIZED SMECTITE-RICH MIXED LAYERS FROM BENTONITE BEDS OF THE CAMPOS BASIN (RIO DE JANEIRO STATE, BRAZIL)

Clays and Clay Minerals ◽

10.1007/s42860-020-00087-5 ◽

2020 ◽

Vol 68 (5) ◽

pp. 446-464

Author(s):

Norbert Clauer ◽

Jan Środoń ◽

Amélie Aubert ◽

I. Tonguç Uysal ◽

Theofilos Toulkeridis

Keyword(s):

Rio De Janeiro ◽

Campos Basin ◽

Mixed Layers ◽

Janeiro State

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AMS-14C measurements for the carbonate platform of the offshore Campos Basin, Rio de Janeiro State, Brazil

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/s0168-583x(00)00274-3 ◽

2000 ◽

Vol 172 (1-4) ◽

pp. 589-591 ◽

Cited By ~ 2

Author(s):

Melayne M. Coimbra ◽

Cátia F. Barbosa ◽

Abı́lio Soares-Gomes ◽

Cleverson G. Silva ◽

Aristóteles Rios-Netto ◽

...

Keyword(s):

Rio De Janeiro ◽

Carbonate Platform ◽

Campos Basin ◽

Janeiro State

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WAVE CLIMATE OFF RIO DE JANEIRO

Coastal Engineering Proceedings ◽

10.9753/icce.v21.17 ◽

1988 ◽

Vol 1 (21) ◽

pp. 17 ◽

Cited By ~ 2

Author(s):

Maria Helena Severo De Souza ◽

Carlos Eduardo Parente Ribeiro

Keyword(s):

Environmental Conditions ◽

Rio De Janeiro ◽

Wave Climate ◽

Offshore Area ◽

Production Region ◽

Wave Data ◽

Campos Basin ◽

The World ◽

Janeiro State ◽

Water Depths

The offshore area northern off Rio de Janeiro State (fig. 1a) is a big oil production region known as Campos basin. In some locations oil is being exploited in water depths of A00 meters, among the largest in the world and new promising fields shall be exploited above 1000 meters. The design and operation of structures and other oceanic systems for such depths is being a big challenge for ocean engineers and the knowledge of environmental conditions is of paramount importance. Wave data is still scarce in the area mainly that concerned with directional spectra.

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Two new Hyalonema species (Hyalonematidae: Amphidiscosida) from eastern and south-eastern Brazil, and further Hexactinellida (Porifera) collected from seamounts off south-eastern Brazil by the RV ‘Marion Dufresne’ MD55 expedition

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315409000253 ◽

2009 ◽

Vol 89 (6) ◽

pp. 1243-1250 ◽

Cited By ~ 8

Author(s):

Konstantin R. Tabachnick ◽

Larisa L. Menshenina ◽

Daniela A. Lopes ◽

Eduardo Hajdu

Keyword(s):

New Species ◽

Atlantic Ocean ◽

Rio De Janeiro ◽

Western Atlantic ◽

South Eastern ◽

First Finding ◽

Campos Basin ◽

Eastern Brazil ◽

Janeiro State ◽

Hexactinellid Sponges

Descriptions of hexactinellid sponges collected by the RV ‘Marion Dufresne’ MD55 expedition on the Vitória–Trindade seamounts chain (off Espírito Santo State, south-eastern Brazil) in 1987 and stored in the MNHN (Muséum National d'Histoire Naturelle in Paris) are presented. Hyalonema (Cyliconema) conqueror sp. nov. (the first finding of this subgenus in the Atlantic Ocean) and H. (Prionema) dufresnei sp. nov. (the second record of this subgenus for the Atlantic Ocean) are described as new species. The holotype of H. (C.) conqueror sp. nov. was collected with a ROV at Campos Basin (off Rio de Janeiro State, south-eastern Brazil), while the paratypes originated from Vitória–Trindade seamounts chain and off Bahía State (eastern Brazil). Other hexactinellids reported here, Farrea sp., Sarostegia aff. oculata, Aphrocallistes aff. beatrix, Dactylocalyx aff. subglobosus and Euplectella suberea were known before to be widely distributed in the Atlantic Ocean. The total number of hexactinellid sponges known from Brazil has risen to 15 and from the south-western Atlantic to 23.

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Hot spot volcanic tracks and their implications for south American plate motion, Campos basin (Rio de Janeiro state), Brazil

Journal of South American Earth Sciences ◽

10.1016/j.jsames.2004.11.006 ◽

2005 ◽

Vol 18 (3-4) ◽

pp. 383-389 ◽

Cited By ~ 15

Author(s):

Antonio Thomaz Filho ◽

Pedro de Cesero ◽

Ana Maria Mizusaki ◽

Joana Gisbert Leão

Keyword(s):

Rio De Janeiro ◽

Hot Spot ◽

Plate Motion ◽

South American ◽

South American Plate ◽

Campos Basin ◽

Janeiro State

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Fe-Ti-V ASSOCIADO AO GABRO DE LÍDICE, ESTADO DO RIO DE JANEIRO

Revista Geonomos ◽

10.18285/geonomos.v24i1.824 ◽

2016 ◽

Author(s):

Ronaldo Mello Pereira ◽

Marcelo dos Santos Salomão ◽

Reiner Neumann ◽

Paulo Guimarães ◽

Enrico Pedroso

Keyword(s):

Magnetic Susceptibility ◽

Rare Earth ◽

Rare Earth Elements ◽

Rio De Janeiro ◽

Chemical Analyses ◽

Ti Oxides ◽

Icp Ms ◽

Opaque Minerals ◽

Titanium Vanadium ◽

Janeiro State

ResumoO Gabro de Lídice corresponde a um corpo tabular, com cerca de 4,0 quilômetros de extensão e espessura entre 100 e 200 metros, constituído por hiperstênio, diopsídio, olivina, plagioclásio e minerais opacos (óxidos de Fe e Ti). Assinaturas petrográfica e geoquímica indicam caráter toleítico, entre os campos alcalino e subalcalino. O enriquecimento em V é de 2 a 3 vezes maior do que o clarck esperado para tal tipo de rocha. O principal óxido é a titanomagnetita, com inclusões e exsoluções de ilmenita. O vanádio concentra-se principalmente na titanomagnetita, variando os teores entre 0,68% e 2,07% de V2O5. Análises ICP-MS em pré-concentrado de titanomagnetita forneceram teores de 50,86% de Fe2O3t, 13,56% de TiO2 e 3.721 ppm de vanádio (~ 0,66% de V2O5). Quimicamente a ilmenita tem conteúdo em Fe2O3t (46,75% a 48,80%) e TiO2 (49,99% a 51,36%). Amostras enriquecidas em titanomagnetita exibem valores dos elementos terras raras e traço 30 vezes inferiores aos observados nas demais amostras. Ao longo de todo o corpo, a susceptibilidade magnética varia em escala centimétrica a decimétrica e está associada a concentrações anômalas de titanomagnetita na rocha, o que pode representar um bandamento magmático. Os dados apresentados sugerem uma origem associada a ambiente intraplaca.Palavras Chave: Gabro, titanomagnetita, ilmenita, titânio, vanádio.AbstractFe-Ti-V ASSOCIATED WITH LIDICE GABBRO, RIO DE JANEIRO STATE. The Gabbro of Lidice has about 4.0 km in length and thickness between 100 and 200 meters, consisting of pyroxene, olivine, plagioclase and opaque minerals (Fe and Ti oxides). Petrographic and geochemical signatures indicate toleitic character, between the alkaline and subalcalino fields. Vanadium enrichment is from 2 to 3 times higher than the expected clarck for such rock. The main oxide is titanomagnetite, with inclusions and exsolutions of ilmenite. Vanadium (0,68% to 2,07% V2O5) is mainly concentrated in titanomagnetite. ICP-MS analyses in pre-concentrated of titanomagnetite provided levels of 50.86% of Fe2O3t, 13.56% of TiO2 and 3,721 ppm of vanadium (~ 0.66% de V2O5). Chemical analyses of ilmenite show content in Fe2O3t (from 46.75% to 48.80%) and TiO2 (from 49.99% to 51.36%). Samples enriched with titanomagnetite display values of trace and rare earth elements 30 times lower than those observed in other samples. Throughout the gabbro, the magnetic susceptibility varies from centimeter to decimeter scales and is associated with abnormal concentrations of titanomagnetite, which may represent magmatic banding. The data presented may suggest an origin associated with intraplate environment.Keywords: Gabbro, titanomagnetite, ilmenite, titanium, vanadium.

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The interaction of the oil and gas offshore industry with fisheries in Brazil: the "Stena Tay" experience

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592008000400004 ◽

2008 ◽

Vol 56 (4) ◽

pp. 289-296 ◽

Cited By ~ 9

Author(s):

Silvio Jablonski

Keyword(s):

Natural Gas ◽

Rio De Janeiro ◽

Oil And Gas ◽

Exclusion Zone ◽

Campos Basin ◽

Oil And Natural Gas ◽

Offshore Industry ◽

Janeiro State

Most of the oil and natural gas produced in Brazil derive from offshore fields, virtually concentrated in the Campos Basin off the coast of Rio de Janeiro State. The area is also of intense fisheries interest, involving participation of hand-liners artisanal boats and tuna boats due to the fish aggregating effect of the oil rigs. In order to avoid accidents with the platform "Stena Tay", in operation at Santos and Campos Basins, in 2001 e 2002, an awareness project was developed aiming at avoiding the presence of fishing boats in its 500 m exclusion zone. This paper summarizes the main observations concerning the extent of the fish aggregating effect and the behavior of the fishing boats in the vicinity of the platform.

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