Estrutura em quilha Brasil central, uma feicao fundamental na geologia de Goias e Tocantins

The older Precambrian geological setting of north Goias/south Tocantins includes three areas of granite-greenstone terrains formed of medium-grade gneisses with associated greenstone belts and nepheline syenitic gneisses, separated by two orogenic belts composing a crustal-scale pop-up structure. The movements were firstly oblique towards NW along the northwestern NNE-SSW-trending Porto Nacional suture, and afterwards of essentially frontal type towards ESE along the southeastern Ceres suture of curved geometry with N-S direction at north and WNW-ESE at the south. The Porangatu block, limited by these sutures, was upthrusted over the neighbouring underthrusted blocks. Three principal kinematic phases are recognized along the orogenic belts. -from English summary

Estratigrafia de seqüências das formações Taciba e Rio Bonito (Membro Triunfo) na região de Mafra/SC, leste da Bacia do Paraná

The Taciba and Rio Bonito (lower Triunfo Mbr) formations are divided into six depositional sequences based on cores, gamma-ray and electrical logs from shallow drillings from northern Santa Catarina State, Each sequence is formed by two systems tracts, a lower one, sandy (lowstand) and an upper one, shaly (highstand). The Taciba Formation has three sequences, S 0 to S 0 sequence S 0 has a thick turbidite sandstone at the base (Rio Segredo Member) that pinches out towards the eastern margin and even disappears in the Mafra outcrop area. Sequence S 1 varies from a thin fluvial-estuarine system to a thick turbidite sandstone of a channelized fan system; S 1 upper shaly system tract is marine in well PP-11, and it is glacially-influenced in well PP-10. Sequence S 2 is a thick sand-stone body of shallow marine origin, but restricted to one well (PP-11); its upper shaly tract is dominated by massive siltstones intercalated with thin, distal tempestites. The lower Triunfo Member (or Taciba-Triunfo transition) begins with the arrival of deltaic clastics of sequence S 3 lower tract, coarsening-up from medial- to proximal delta front sandstones. Sequence S 4 is quite similar to S 3, both showing sand-stone progradation from north to south, as opposed to the southwest-sourced transgressive diamictites. Sequence S 5 consists of fluvial deposits at well PP-12, and two transgressive cycles from wells PP-11 to PP-9, each one of them composed of fluvial-estuarine to marine systems. Well PP-10 is an exception, where the lower cycle presents deglaciation to marine deposits.

Ciclos e seqüências deposicionais das formações Rio da Batateira e Santana (Andar Alagoas), Bacia do Araripe, Brasil

The Rio da Batateira e Santana formations, the latter with Crato, Ipubi and Romualdo members (Alagoas Stage, Aptian), were studied in four cored and logged wells from the eastern portion of Araripe Basin, Northeastern Brazil. The investigated section is 230 m-thick, and PS-14 well is the most representative, because it is the only one which sampled the evaporites of Ipubi Member. Nine facies cycles were identified, being formed by siliciclastics (estuarine, deltaic and lacustrine), mixed lithologies (lacustrine), carbonates, black shales and marls (lacustrine), and gypsum-anhydrite (lacustrine evaporite). The ordering of facies cycles furnished six depositional sequences. They were formed by siliciclastic, regressive-transgressive R-T cycles (S1 and S4, corresponding to Rio da Batateira Formation and to Santana Formation/Romualdo Member), by siliciclastics and carbonates, R-T cycles (S2, S3.1 and S3.2, corresponding to Crato Member), and by siliciclastic-carbonate, R-T cycles followed by evaporitic cycles (S3.3, referred to Ipubi Member). The last cycles correspond to concentration-dilution, C-D cycles of marine brines, which precipitated gypsum in the restricted lacustrine basin.

Cursos de geologia: expansão, interiorização e consolidação do ensino de geologia no brasil

A short time after the creation of the first Geology courses in Brazil (in 1957 with the pioneers in the University of São Paulo and in the Federal Universities of Ouro Preto, Pernambuco and Rio Grande do Sul, and then in the following year in the Federal Universities of Bahia and Rio de Janeiro), there arose other initiatives that spread almost twenty Geology courses throughout Brazil. In addition to expanding the Geology teaching in the South, Southeast and Northeast regions, these initiatives succeeded in allowing access to geological education for the population in the North and Central-west of Brazil. In the 1960s, the courses in the Federal University of Para in Belém (1964), University of Brasilia (1965) and São Paulo State University in Rio Claro (1969) were implanted. In the following decade, the courses in the Federal Rural University of Rio de Janeiro in Seropédica (1970), the Federal University of Ceará in Fortaleza (1970), the University of Rio dos Sinos in São Leopoldo (1973), the Federal University of Paraná in Curitiba (1973), the Federal University of Minas Gerais in Belo Horizonte (1973), the Federal University of Amazonas in Manaus (1976), the Federal University of Mato Grosso in Cuiabá (1976), the Federal University of Rio Grande do Norte in Natal (1976), and the State University of Rio de Janeiro in Rio de Janeiro (1977) were all created. At the close of the twentieth century, the course was implanted in the State University of Campinas (1998). Now, at the beginning of the twenty-first century, new Geology courses are being implanted, accentuating the movement inland of Geology teaching in Brazil. The Federal University of Pará began a new course in its campus in Marabá in the south-east of Pará and the Federal University of Bahia implanted a new course in its campus in Barreiras in the west of Bahia. Finally, the Federal Universities of Sergipe, Espírito Santo and Roraima commenced Geology courses in Aracaju, Alegre and Boa Vista, respectively. This chapter will present the synthesis of the Geology courses which, over the last decades of the twentieth century, contributed to the expansion of Geology teaching in the country, taking it to every region and giving opportunities to a large number of Brazilian citizens to realize their dreams and tread the paths of their professional vocation.

Geologia e litogeoquímica da formação serra geral nos estados de mato grosso e mato grosso do sul

The basalts of the Formação Serra Geral in Parana Basin in the Mato Grosso do Sul and Mato Grosso states cover an area of 180,000 km2. They rest on the Botucatu sandstones and they are recovered by the sedimentary rocks of Bauru and Caiuá Groups. The mineralogical composition of these rocks are plagioclase (40%-55%), clinopyroxenes (19%-40%; augite and pigeonite), opaque minerals (2%-10%; magnetite and ilmenite) and olivine (1.5%). Geochemical data show two different types of basalts, named ATi-Pitanga (2.6% < TiO2 < 4.2%; 396 ppm < Sr < 438 ppm) and BTi-Ribeira (1.7% TiO2 <2.4%, 246 ppm < Sr < 286 ppm). In general, ATi-Pitanga have gently higher La/Yb(n) (6,1 ± 1,5ppm) than those BTi-Ribeira (5.6 ± 1,7ppm). The geochemical differences between ATi-Pitanga and BTi-Ribeira probably are related to different degrees of partial melt of a same mantle source, or to different mantle sources. The field relations show that BTi-Ribeira is displaced towards the north-western margin of the Paraná Basin and the thickness of lava flows increases towards the Paraná Graben, suggesting that ATi-Pitaga overlies BTi-Ribeira.

Geologia e Caracterização Tecnológica do Minério de Manganês da Mina Córrego do Cocho, Itapira (SP)

The objects of this study are three manganese ore deposits and one mine derived from lateritic weathering of gondites (spessartine quartzites). These deposits are associated with Mn-rich garnet metasediments of the Itapira Group (Paleoproterozoic) and the reserves were estimated at approximately 2.0 × 10 6 tons with an average grade of 23% MnO 2. The ore minerals are cryptomelane, pyrolusite, lithiophorite, spessartine and psilomelane. Several crystal shapes and textural characteristics were identifi ed in this study, which are related to the degree of liberation, as confi rmed by heavy media separation method. In this study, we determined the main characteristics of the liberation of manganese, which is concentrated in the fi ne grain-size fraction and is lost during ore dressing. Therefore, the low average content of MnO 2 (28%) is due to this loss, whereas at grain size of minus 0.074 mm, contents near 40% MnO 2 were observed. This suggests that the ore can be used for manufacturing manganese sulphate fertilizers. A comparative study with the ore deposits located at Ouro Fino (MG), mainly with the Caneleiras mine, showed that higher degree of liberation occurs in the coarse grain-size fractions (0.84 to 0.074 mm with MnO 2 content of 38%). As a consequence, the ore can be used for manufacturing Fe-Si-Mn alloys.

Carta geoambiental (1:50.000) e trilhas interpretativas da zona turística do Vale do Pati, Chapada Diamantina-BA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Processos, fácies e geometria do sistema turbidítico da formação Taciba/Membro Rio Segredo, faixa aflorante norte catarinense

Pós-graduação em Geociências e Meio Ambiente - IGCE

Vertebrados fósseis do estado de Goiás, com ênfase em sua fauna de amniotas, compreendida entre o período permiano e a época pleistoceno

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caracterização estrutural da porção sul do greenstone belt de Guarinos, GO

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Geologia e potencialidade do granito Vermelho Capão Bonito (Sudoeste do Estado de São Paulo) como rocha ornamental

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Geologia estrutural aplicada às rochas ornamentais na Pedreira Knawa, Cláudio (MG)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Revisão dos Testudines fósseis do cretáceo superior da Bacia Bauru, com a descrição preliminar de novo morfótipo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Geologia e mineralogia de pegmatito mineralizado em estanho e metais associados (Nb, Ta, Zn, Cu, Pb), Mina Bom Futuro, Rondônia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Litoestratigrafia da bacia do Araripe: reavaliação e propostas para revisão

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)