Results 81 to 90 of about 127 (117)

Geochemistry and petrology of ultramafic lamprophyres from Schirmacher Oasis, East Antarctica

Mineralogy and Petrology, 1999
Petrographic and geochemical data are presented for some ouachitites from the Schirmacher Oasis. The studied dike intruded into the metamorphic basement of the East Antarctic craton. The ouachitite samples contain substantial amounts of zoned phlogopite and diopsidic to salitic pyroxene as phenocrysts.
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Alkaline ultramafic lamprophyres and associated carbonatite dykes from the Kalix area, northern Sweden

Geologische Rundschau, 1981
Alkahne ultramafic lamprophyres and associated carbonatite dykes form north-south trending dyke swarms. The lamprophyres are sub-divided into micaceous, picritic and breccia varieties. Carbonatites sensu stricto (beforsites) occur very subordinate.
Peter Kresten, Erik åhman, Arild O. Brunfelt   +2 more
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Trace elements in olivine of ultramafic lamprophyres controlled by phlogopite-rich mineral assemblages in the mantle source

Lithos, 2017
Abstract Carbonate-rich ultramafic lamprophyres (aillikites) and associated rocks characteristically occur during the early stages of thinning and rifting of cratonic mantle lithosphere, prior to the eruption of melilitites, nephelinites and alkali basalts.
Marina Veter, Stephen F. Foley, Regina Mertz-Kraus, Nora Groschopf   +3 more
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Olivine in ultramafic lamprophyres: chemistry, crystallisation, and melt sources of Siberian Pre- and post-trap aillikites

Contributions to Mineralogy and Petrology, 2018
We studied olivines from the Devonian pre-trap (the Ilbokich occurrence) and the Triassic post-trap (the Chadobets occurrence) carbonate-rich ultramafic lamprophyres (UMLs) in the southwestern portion of the Siberian craton. On the basis of detailed investigations of major, minor, and trace-element distributions, we have reconstructed the main ...
A. A. Nosova, L. V. Sazonova, A. V. Kargin, M. D. Smirnova, A. V. Lapin, V. D. Shcherbakov   +5 more
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Petrogenesis of ultramafic lamprophyres and carbonatites of the Alnö complex (central Sweden)

Goldschmidt2022 abstracts, 2022
Lukáš Krmíček, Tomáš Magna, Jindřich Kynický, Michaela Vašinová Galiová, Valentin Troll   +4 more
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Composition of Phlogopite from Ultramafic Lamprophyres as an Indicator of Formation Conditions (Zima Alkaline Ultramafic Carbonatite Complex, Southern Siberian Craton)

Russian Geology and Geophysics
Abstract ––The paper presents data on the age and composition of phlogopite from dikes of ultramafic lamprophyres (aillikites) of the Zima Complex located within the Urik–Iya graben in the East Sayan region (southern margin of the Siberian craton).
Ya.N. Nugumanova, A.G. Doroshkevich, A.E. Starikova, A.V. Ponomarchuk   +3 more
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ALTERATION IN ULTRAMAFIC LAMPROPHYRES AND ITS CONTROL ON REE DISTRIBUTION IN WESTERN KENTUCKY

Geological Society of America Abstracts with Programs, 2023
Zachary Walton, Georgina Lukoczki, Craig Dietsch   +2 more
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Petrology of Late Jurassic allochthonous ultramafic lamprophyres within the Batain Nappes, Northeastern Oman

International Geology Review, 2016
ABSTRACTLate Jurassic ultramafic lamprophyre (UML) sills and dikes occur as 3 km-long intrusions within the allochthonous Whara Formation of the Batain nappes, eastern Oman. The sills and dikes comprise macrocrystic phlogopite and spinel-bearing aillikite and damtjernite.
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Perovskite Geochronology and Petrogenesis of the Neoproterozoic Mad Gap Yards Ultramafic Lamprophyre Dykes, East Kimberley Region, Western Australia

Contributions To Mineralogy and Petrology, 2023
Michael Verrall, William L. Griffin, Cristina Talavera   +2 more
exaly  

Alkaline and ultramafic lamprophyres in Italy: Distribution, mineral phases, and bulk rock data

2008
Several lamprophyre outcrops occur in Italy paralleling the European cycles. Lamprophyre occurrences from the lower Cretaceous to the Oligocene are comprised primarily of dykes and rarely lavas, generally emplaced in isolation. They are ultramafic or alkaline lamprophyres located in eight different places ranging from the eastern Alps to the areas of ...
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