Results 41 to 50 of about 7,100 (219)
Subducted and recycled lithosphere as the mantle source of ocean island basalts from southern Polynesia, central Pacific [PDF]
, 1989 L'étude géochimique et pétrographique des basaltes des archipels volcaniques de la Polynésie Française montre que ces roches dérivent d'une lithosphère ancienne ayant subi une subduction et un recyclage. La composition chimique et isotopique des basaltes
Barsczus, Hans Gustave +4 more
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AnalectaThe presence of kimberlites in the Democratic Republic of Congo has been known since buttgenbach reported a typical ‘yellow ground’ in Katanga as early as 1908, and prospecting work before and after 1914 had already identified twenty-four pipes in ...
Onya Ngila Arnold +6 more
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Geochemistry, Geophysics, Geosystems, 2015 Different versions of a composite apparent polar wander (APW) path of variably selected global poles assembled and averaged in North American coordinates using plate reconstructions show either a smooth progression or a large (∼30°) gap in mean ...
Dennis V. Kent +4 more
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Geochemistry, Geophysics, Geosystems, 2014 Both silicate melts and aqueous fluids are thought to play critical roles in the chemical differentiation of the Earth's crust and mantle. Yet their relative effects are poorly constrained. We have addressed this issue by measuring partition coefficients
John Adam +4 more
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THE FEATURES OF THE INDICATOR MINERALS OF KIMBERLITES IN A NEW PIPE YANVARSKAJA (WESTERN YAKUTIA)
Известия высших учебных заведений: Геология и разведка, 2017 The first results of the mineral-petrographic studies of microclastes of kimberlites from the basal horizon of the Upper Paleozoic deposits of the Alakit-Markhinsky kimberlite field (Western Yakutia) have been presented.
D. V. Ivanov +2 more
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Groundmass Chromospinellides from Kimberlites of Khompu-May Kimberlite Field
IOP Conference Series: Earth and Environmental Science, 2021 Abstract The current paper presents the results of studying chromites of kimberlite mesostasis forming the Manchary, Aprelskaya, Erel, Turakhskaya, and Artemova pipes within the Khompu-May kimberlite field (central Yakutia). Despite shared texture and structural characteristics and mineral composition of the kimberlites, chromospinellide
Nikolay Oparin, Oleg Oleynikov
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, 2015 It is suggested that the Tunguska event in June 1908 cm-large was due to a cm-large ball of a condensate of bound states of 6 top and 6 anti-top quarks containing highly compressed ordinary matter. Such balls are supposed to make up the dark matter as we
Froggatt, C. D., Nielsen, H. B.
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Руды и металлыPossibilities of the infrared microscopy technique as applied to the express diagnostics of diamond crystals and of grains of most of its satellite minerals, extracted from heavy mineral concentrate (HMC) samples, are considered. An original technique of
Khachatryan G. K., Anashkina N. E.
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Geosystems and Geoenvironment, 2022 We have re-visited the ‘diamondiferous kimberlite’ from the Jamnidih area of Mahasamund, Bastar Craton, Central India. This study presents detailed field observations, petrographic and geochemical studies of Jamnidih rocks in view of the reported ...
Mahendra Kumar Singh +3 more
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ガーナ, ビルム・ダイヤモンド産地のアクァティア地域に分布する沖積層の重鉱物分析 [PDF]
, 2005 Heavy mineral analysis was carried out on Pliocene to Recent alluvial sediments from the Birim diamondiferous field od Ghana. The main objective of the study was to examine the mineral composition of heavy fractions in order to identify : (1) the heavy ...
Bruce, Banoeng-yakubo +3 more
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