Results 41 to 50 of about 382 (174)
Nature, 1962 Recently, von Knorring and du Bois described a vesicular lava of high carbonate content from western Uganda which shows close geochemical affinities with intrusive carbonatites. They stated: "It must be emphasized that the lavas examined are fresh and unaltered and that the carbonated nature cannot be attributed to alteration after solidification ...
Wyllie, P. J., Tuttle, O. F.
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Литосфера, 2015 Type-chemical features of high-titanium magnezium-ferruginous micas of granulites, mafite-ultramafites, alkaline rocks, and carbonatites are considered.
A. I. Belkovsky
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Геодинамика и тектонофизика, 2018 The TerraneChrone® (LA-ICP-MS) technique has been applied to carry out an integrated study of detrital zircons in sandstones sampled from the basal horizons of the stratotypical Riphean sequence in the Southern Urals, specifically the Navysh and Chudin ...
T. V. Romanyuk +4 more
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MINERALS ASSOTIATIONS AND COMPOSITIONAL HETEROGENEITY OF ZIRCON FROM MIASKITE-CARBONATITE COMPLEX OF THE VISHNEVYe MOUNTAINS, SOUTH URALS [PDF]
Минералогия, 2019 In alkaline rocks, pegmatites and carbonatites of the Vishnevye Mountains, zircons co-crystallized with rock-forming silicates (feldspars, nepheline, annite, etc.), as well as with some other minerals (pyrochlore, magnetite, ilmenite, apatite, monazite ...
V.I. Popova, V.A. Popov, V.A. Kotlyarov
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Frontiers in Earth ScienceThe Bayan Obo Fe-REE deposit, a world-renowned giant polymetallic ore concentration area, is located on the northern edge of the North China Craton, which borders on the Central Asian orogenic belt.
Chenghao Ren +5 more
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To the problem of origin of the Bug series rocks
Геофизический журнал, 2019 The age of the Bug series rocks is an object for discussion. Isotopic methods do not give a distinct answer, because in the same outcrop, the same sample and even in the same crystal of zircon several dates of formation are to be found with evident ...
O. V. Usenko
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Journal of the Geological Society of India, 2019 ABSTRACT Based on the field relations, associated rock types and age, the carbonatite-alkaline rock complexes of India, that are spatially related to deep main faults, rifts and shear zones, have been classified in to two major groups, namely: 1. Middle – late Cretaceous, subvolcanic – volcanic complexes (Amba Dongar, Siriwasan, Swangkre,
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Brazilian Journal of Geology, 2021 We present airborne magnetic and radiometric characteristics of some igneous suites from the Ponta Grossa Arch Alkaline Province (southern Brazil), namely the Bairro da Cruz, Banhadão, Barra do Itapirapuã, Mato Preto and Tunas complexes, Barra do ...
Vinicius Antunes Ferreira da Silva +1 more
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DISTRIBUTION OF TRACE ELEMENTS IN PEROVSKITE FROM SKARNS AND CALCITE VEINS OF THE CHERNAYA RECHKA AND NAZYAM RIDGES (SOUTH URALS) [PDF]
Минералогия, 2017 Trace element distribution and crystal morphology of perovskite from garnet-vesuvianite skarn of the Akhmatovskaya mine and chlorite-perovskite-calcite veins of the Perovskitovaya mine (South Urals) were studied using LA-ICP-MS.
S.Yu. Stepanov +3 more
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New Zealand Journal of Geology and Geophysics, Volume 69, Issue 2, June 2026.Clasts of albite‐porphyroblastic quartzofeldspathic schist, derived from the Otago Schist basement, occur within the Port Chalmers Breccia, a diatreme at the centre of the Dunedin stratovolcano, New Zealand. Schists have undergone varying degrees of replacement reactions (at temperatures of 300° to >500°C) producing hornfelses, with Ca‐ and K‐enriched ...
Alan F. Cooper
wiley +1 more source