18 documents found, page 1 of 2
Petrografia e litoquímica das formações ferríferas bandadas da região de Quixer...
Veríssimo, César Ulisses Vieira; Magini, Christiano; Parente, Clóvis Vaz; Nogueira Neto, José de Araújo; Almeida, Afonso Rodrigues deTwo new occurrences of banded iron formations (BIF’s) had been identified in the regions of Quixeramobim and Boa Viagem, Ceará State. The occurrences are associated to the Neoarchean to Paleoproterozoic rocks of the Cruzeta Complex, whose Sm/Nd - TDM model ages vary between 2,3 and 3,2 Ga. The chemical analyses of major elements in six samples show a relatively simple chemical composition, with SiO 2 and Fe2O3 ...
Resistência ao ataque químico de granitos ornamentais do stock Serra do Barriga...
Mattos, Irani Clezar; Nogueira Neto, José de Araújo; Artur, Antonio Carlos; Silva Filho, Juvenal Carolino daHere is presented results from resistance to chemical attack provided by four types of granitic stock Serra do Barriga, through the loss of luster, color variations, minerals alterations, beyond the influence of petrography. Chemical reagents were used simulating the effects caused by cleaning products or organic substances on the granites. Although we have differences in grain and the mineralogical proportions...
Parâmetros normativos das rochas ornamentais pegmatíticas do Seridó Oriental Pa...
Leal Neto, Antonio; Mattos, Irani Clezar; Silva, Francisco Diones Oliveira; Clemente, Igor Magalhães; Nogueira Neto, José de AraújoThe rocks studied in the present work are known commercially as White Fuji, Capuccino Fuji and Golden Fuji. They come from the same mining front located in the municipality of Pedra Lavrada/PB. They have a similar mineral composition, consisting mainly of quartz, plagioclase, muscovite, microcline and garnet with modal composition between 5% and 34% and accessory minerals, with a modal composition of less than ...
Petrografia e química mineral do Stock Granítico Serra do Barriga (Sobral, CE, ...
Mattos, Irani Clezar; Nogueira Neto, José de Araújo; Artur, Antonio CarlosPetrography and mineral chemistry of Serra do Barriga Granitic Stock (Sobral, CE, northeast of Brasil). The Serra do Barriga Granitic Stock (SGSB), located at NNW of the Ceará, northeast of Brazil, presents faciological variation that permits commercial exploitation in four types of ornamental rocks: Rosa Iracema (RI), Rosa Olinda (RO), Branco Savana (BS) and White Crystal Quartz (BCQ). The aim of this paper is...
Sustentabilidade ambiental da extração de áridos: a lavra de areia no canal ati...
Nobre Filho, Pedro Aguiar; Sabadia, José Antonio Beltrão; Duarte, Cynthia Romariz; Magini, Christiano; Nogueira Neto, José de AraújoThis study analyzes the environmental sustainability of sand extraction along the active bed of Canindé river, Paramoti municipality, Ceará. The mined material was sampled, characterized and qualified for use as aggregate in construction. The deposit was cubed, resulting in measured reserves, indicated and total one. The sand extraction is carried out continuously in the active bed of the Canindé river, since t...
The Itataia phosphate-uranium deposit (Ceará, Brazil) new petrographic, geochem...
Veríssimo, César Ulisses Vieira; Santos, Roberto Ventura; Parente, Clóvis Vaz; Oliveira, Claudinei Gouveia de; Cavalcanti, José Adilson DiasThe Itataia phosphate-uranium deposit is located in Santa Quiteria, in central Cear a State, northeastern Brazil. Mineralization has occurred in different stages and involves quartz leaching (episyenitization), brecciation and microcrystalline phase formation of concretionary apatite. The last constitutes the main mineral of Itatiaia uranium ore, namely collophane. Collophanite ore occurs in massive bodies, len...
Caracterização petrográfica e tecnológica de granitosornamentais do stock graní...
Mattos, Irani Clezar; Artur, Antonio Carlos; Nogueira Neto, José de AraújoPetrographic analysis and technological behaviour of four varieties of granitic dimension stones from Serra da Barriga stock, in NNW Ceará State, Brazil, are presented in this work. The investigated rock types are commercially known as Rosa Iracema, Rosa Olinda, Branco Savana and Branco Cristal Quartzo and are classified as isotropic, inequigranular syenogranites and monzogranites, medium to coarse grained, wit...
Organic and isotopic geochemistry of evaporites and shales of the Santana Group...
Pontes, Naedja Vasconcelos; Chagas, Daniel Bezerra das; Souza, Ana Clara Braga de; Nascimento Junior, Daniel Rodrigues doEven being the more studied of the interior basins of Northeast Brazil, the Araripe Basin still lacks research in organic geochemistry designed to support interpretations of depositional systems and conditions of formation. This work aims to investigate the organic behavior of evaporites and shales from the Santana Group (Lower Cretaceous), as well as discuss their role in the evolution of its depositional syst...
Petrography and mineral chemistry of serra do Barriga granitic stock (Sobral, C...
Mattos, Irani Clezar; Nogueira Neto, José de Araújo; Artur, Antonio Carlos [UNESP]Made available in DSpace on 2022-04-29T08:27:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-09-01; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); The Serra do Barriga Granitic Stock (SGSB), located at NNW of the Ceará, northeast of Brazil, presents faciological variation that permits commercial exploitation in four types of ornamental rocks: Rosa Iracema (RI), Rosa Olinda (RO),...
Caracterização da mistura de argilas e rejeitos da pedra Cariri: resultados pre...
Livalter, Eulivana Assunção; Lima, Zilma Mendes de; Nogueira, Ricardo Emílio Ferreira Quevedo; Nogueira Neto, José de Araújo; Sasaki, José MarcosThis work presents the characterization of clays from Cariri region (State of Ceará-Brazil) and the production of composite materials formed by this clays and Cariri Stone (Limestone), aiming the use of rejects produced during the Cariri rock extraction process to the fabrication of red ceramics. Samples with different concentrations of Cariri rock (10%, 15%, 20% and 30%) dispersed in clays have been prepared, ...