Results 231 to 240 of about 50,766 (267)

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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A U–Pb age for mineralized Nipissing diabase, Gowganda, Ontario

Canadian Journal of Earth Sciences, 1986
Concordant baddeleyite and rutile analyses from mineralized Nipissing diabase at Gowganda's Castle mine yield a U–Pb age of [Formula: see text]. Baddeleyite is a primary phase of the diabase; therefore the age dates the magmatic emplacement. The genesis of rutile is less certain: rutile could have formed during an episode of alteration, veining, and ...
F. Corfu, A. J. Andrews
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Discordant Zircon U–Pb Ages from the Uganda Basement

Nature Physical Science, 1971
FOR several years there has been controversy about the ages of the Uganda basement gneisses. Potassium–argon ages of micas from the basement rocks1 range from 600 to 415 m.y. whereas results for the apparently unconformably overlying Karagwe–Ankolean and Buganda–Toro sedimentary systems2,3 to the south (around the north end of Lake Victoria) suggest an
P. J. LEGGO, M. AFTALION, R. T. PIDGEON
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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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Biological age is increased by stress and restored upon recovery

Cell Metabolism, 2023
Tong Gong
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