Results 231 to 240 of about 53,720 (266)

A minimum UPb age for Siberian flood-basalt volcanism

Geochimica et Cosmochimica Acta, 1996
Abstract Establishing an accurate and precise age for Siberian flood-basalt volcanism is of great importance in evaluating causes for the unequaled mass extinction of flora and fauna at the Permian-Triassic boundary. We report a new, minimum UPb age obtained from zircon and baddeleyite from the mineralized Noril'sk I intrusion that cuts the lower ...
S.L. Kamo, G.K. Czamanske, T.E. Krogh
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U–Pb age of titanite in the Mylonite Zone, southwestern Sweden

Geologiska Föreningen i Stockholm Förhandlingar, 1993
Abstract U–Pb dating of titanite from a mafic lens in the Mylonite Zone in southwestern Sweden yields an almost concordant age of c. 920 Ma. The titanite formed during retrogression of granulite-to amphibolite-facies rocks. Sources for Ti and Ca in titanite were Fe-Ti oxides and relatively grossular-rich garnets, respectively.
Leif Johansson, Åke Johansson
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Zircon UPb ages of Guyana greenstone-gneiss terrane

Precambrian Research, 1982
Abstract Isotopic UPb studies of zircons collected from weathered metagreywackes of the Barama-Mazaruni Supergroup of northern Guyana, South America, demonstrate an age of origin of ca. 2250 Ma. This is the best estimate for the age of the associated metavolcanic rocks.
Allan K. Gibbs, William J. Olszewski
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U-Pb age of autochthonous paleoproterozoic charnockite in the Aldan Shield

Doklady Earth Sciences, 2012
Autochthonous and parautochthonous charnockites in granulite facies of the Aldan Shield (the Aldan River upper flow) were dated. According to the geological observation data, the autochthonous and parautochthonous granite formation included successive development of nebulite (Lc1), its melting product such as early diatectite (Lc3), later “layer-by ...
V. A. Glebovitskii, I. S. Sedova, N. G. Berezhnaya, A. N. Larionov, N. G. Rizvanova, L. M. Samorukova   +5 more
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U–Pb ages for magmatism and deformation in the New Quebec Orogen

Canadian Journal of Earth Sciences, 1997
The New Quebec Orogen is a Paleoproterozoic fold and thrust belt, active from 2.17 to 1.77 Ga, bordering the eastern margin of the Archean Superior Province. The orogen developed on a long-lived, passive continental margin and comprises two volcanic – sedimentary sequences.
N. Machado, T. Clark, J. David, N. Goulet   +3 more
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U-PB EMPLACEMENT AGES OF KANSAS LAMPROITES AND KIMBERLITES

Geological Society of America Abstracts with Programs, 2023
Isabella Lupini, Pamela D. Kempton, Andreas Möller, Claudia Adam   +3 more
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Microstructures and U-Pb ages of phosphates in Apollo 14 breccias

Goldschmidt2023 abstracts, 2023
Fiona Thiessen, Steven Goderis, Martin Whitehouse, James Carpenter   +3 more
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UNMIXING DETRITAL ZIRCON U-PB AGE DISTRIBUTIONS

Geological Society of America Abstracts with Programs, 2017
Kurt E. Sundell, Joel E. Saylor
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Study Identifies Signs and Symptoms of Colorectal Cancer Risk at Younger Ages

Ca-A Cancer Journal for Clinicians, 2023
Mike Fillon
exaly  

DETERMINING THE U-PB EMPLACEMENT AGE OF LAMPROITES IN SOUTHEASTERN KANSAS

Geological Society of America Abstracts with Programs, 2022
Isabella Lupini, Pamela Kempton, Andreas Möller, Claudia Adam   +3 more
openaire   +1 more source