Results 61 to 70 of about 2,200 (203)

Geocronologia do complexo máfico-ultramáfico alcalino de Santa Fé, Goiás

Boletim IG, 1979
The Santa Fe mafic-ultramafic alkaline complex, Goias, is a subcircular body with a rough concentric zoning of rock types, containing dunites at the center and peridotites and pyroxenites at the border. Minor rock types associated with the major units are missourites, malignites and phonolites. An essexitic body occurs as a small intrusion close to the
Aledir P Barbour, Vicente A. V Girardi, Koji Kawashita, Ana Maria S. de Souza   +3 more
openaire   +1 more source

High spatial resolution analysis of Pb and U isotopes for geochronology by laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS)

Anais da Academia Brasileira de Ciências, 2009
Age determinations using the 235U and 238U radioactive decay series to the daughter isotopes 207Pb and 206Pb, respectively, using the mineral zircon (ZrSiO4), are widely used to decipher geological processes.
Bernhard Bühn, Márcio M. Pimentel, Massimo Matteini, Elton L. Dantas   +3 more
doaj   +1 more source

Geocronología y Paleontología de la formación Novillo, Noreste de México

Paleontología Mexicana
El reporte dudoso de Gryphaea nebrascensis (sin probar), estableció equívocamente la edad Oxfordiano a estratos de la formación Novillo en el noreste mexicano.
S. E. D. de Antuñano, J. R. Pantoja-Irys, F. J. Vega   +2 more
semanticscholar   +1 more source

Geocronologia de ortognaisses peraluminosos do Tipo-S associados ao Grupo Araxá na região sudeste do estado de Goiás, Faixa Brasília: cristalização versus herança

Geosciences = Geociências
RESUMO: Na região sudeste do Estado de Goiás, nos municípios de Mairipotaba e Cromínia, ocorrem corpos de ortognaisse intercalados em rochas metassedimentares do Grupo Araxá, agrupados regionalmente sob a denominação de Granitoides tipo Aragoiânia e ...
Guillermo Rafael Beltran Navarro, Thaís Güitzlaf Leme, A. Zanardo   +2 more
semanticscholar   +1 more source

Geocronologia de grandes Províncias ígneas no NE do Brasil

, 2022
The formation of large igneous provinces (LIPs) is directly associated with global geological events that include rupture of (super)continents, opening of oceans and biotic crises.
Oliveira, Alisson Lopes
core   +1 more source

Geocronologia u-pb del Plutone della Valle del Cervo (Biella) [PDF]

, 2015
I complessi intrusivi alcalini, e i loro prodotti di alterazione, costituiscono una delle principali risorse di materie prime ad alto valore economico. Il magmatismo alcalino è di solito associato a fenomeni di rifting continentale che può essere legato ...
Stagliano', Antonella
core  

Superposition of structures in the interference zone between the southern Brasília belt and the central Ribeira belt in the region SW of Itajubá (MG), SE Brazil

Brazilian Journal of Geology
: The study area is localized in the Socorro nappe, part of the southern Brasília belt, with a minor part in the Embu terrane, part of the central Ribeira belt. Three phases of deformation were detected, Dn-1, Dn and Dn+1.
Rodrigo Vinagre, Rudolph Allard Johannes Trouw, Hugo Kussama, Rodrigo Peternel, Julio Cezar Mendes, Patrícia Duffles   +5 more
doaj   +1 more source

Evolução tectônica do Cinturão Dom Feliciano no Sul do Brasil: relações geológicas e geocronologia U-Pb

, 2016
The Dom Feliciano Belt is an important Neoproterozoic to Cambrian orogenic complex, extending from eastern Uruguay to southern Brazil. It comprises a collage of oceanic domains and continental fragments developed between 900 and 540 Ma between the Rio de
R. P. Philipp, Márcio Martins Pimentel, F. Chemale   +2 more
semanticscholar   +1 more source

Arquitectura estratigráfica, ambientes de depósito y geocronología de la Formación Olinalá (Pérmico tardío), noreste de Guerrero, México

, 2020
The Olinalá Formation is a marine-continental Permian sedimentary succession of ~860 m thick, which is exceptionally exposed in the northeast of the Guerrero state, in southern Mexico.
Edgar Juárez-Arriaga, Gustavo Murillo-Muñetón   +1 more
semanticscholar   +1 more source

U-Pb SHRIMP and 40Ar/39Ar constraints on the timing of mineralization in the Paleoproterozoic Caxias orogenic gold deposit, São Luís cratonic fragment, Brazil

Brazilian Journal of Geology
Caxias is an orogenic gold deposit in the São Luís cratonic fragment, which is correlated with the Rhyacian terranes of the West-African Craton. The deposit postdates peak metamorphism (estimated at 2100 ± 15 Ma) and is hosted in a shear zone that cuts ...
Evandro Luiz Klein, Colombo Celso Gaeta Tassinari, Paulo Marcos Vasconcelos   +2 more
doaj   +1 more source