Results 21 to 30 of about 646 (177)

Carbonatitic Lavas [PDF]

open access: yesNature, 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.
openaire   +2 more sources

PHOSPHATE-FLUORIDE-CARBONATE MINERALIZATION IN LAMPROITE ROCKS OF THE RYABINOVY PLUTON (CENTRAL ALDAN): MINERALOGICAL AND GEOCHEMICAL FEATURES AND ORIGIN [PDF]

open access: yesМинералогия, 2017
Carbonate and apatite-fluorite mineral assemblages are studied in lamproite rocks from high-K Ryabinovy intrusive (Central Aldan, Russia). It is concluded that these assemblages are genetically related and belong to the same apatite-fluorite-carbonate ...
I.F. Chayka, A.E. Izokh
doaj  

Early carbonatite magmatism at Oldoinyo Lengai volcano (Tanzania): carbonatite–silicate melt immiscibility in Lengai I melt inclusions

open access: yesComptes Rendus. Géoscience, 2021
Carbonatites are unusual C-rich alkaline magmas that have been reported throughout the geological record. Nevertheless, there is only one currently active carbonatite system on Earth: Oldoinyo Lengai stratovolcano in northern Tanzania (God’s mountain in ...
France, Lydéric   +2 more
doaj   +1 more source

Geology and Geochemistry of the Early Proterozoic Kortejärvi and Laivajoki Carbonatites, Central Fennoscandian Shield, Finland [PDF]

open access: yesBulletin of the Geological Society of Finland, 1997
This paper provides for the first time extensive petrological, mineralogical and geochemical data on the early Proterozoic Kortejärvi and Laivajoki carbonatites, northern Finland, which form metamorphosed and highly strained bodies 2 and 4 km long within
J. Nykänen, K. Laajoki, J. Karhu
doaj   +1 more source

Spatial and temporal distribution, geochemical characteristics of carbonatites and their relationship with U–REE mineralization in the Xiaoqinling area, Shaanxi Province

open access: yesDizhi lixue xuebao
[ Objective ] Carbonatites, as magmatic-origin rocks, are crucial source rocks for uranium, rare earth, and other minerals. They are widely distributed in the Xiaoqinling region of Shaanxi, giving rise to numerous large to super-large carbonatite ...
KANG Qingqing   +7 more
doaj   +1 more source

Remote Sensing Exploration of Nb-Ta-LREE-Enriched Carbonatite (Epembe/Namibia)

open access: yesRemote Sensing, 2016
On the example of the Epembe carbonatite-hosted Nb-Ta-LREE deposit, we demonstrate the use of hyperspectral reflectance data and geomorphic indicators for improving the accuracy of remote sensing exploration data of structurally-controlled critical raw ...
Robert Zimmermann   +4 more
doaj   +1 more source

Ore specialization of carbonatite complexes at the Urais and Timan

open access: yesЛитосфера, 2017
The ore specialization of carbonatite complexes of Urals-Timan region has been established: niobium and rare earth-niobium - for the Urals’ carbonatite complexes, the rare-earth - for carbonatites of Timan.
I. L. Nedosekova   +2 more
doaj   +2 more sources

The composition of apatite in the Archean Siilinjärvi glimmerite-carbonatite complex in eastern Finland [PDF]

open access: yesBulletin of the Geological Society of Finland
We present a geochemical dataset and cathodoluminescence images of apatite from the Neoarchean (2610 Ma) glimmerite-carbonatite rocks from the Siilinjärvi complex, Eastern Finland. The subhedral, tapered prismatic grains are compositionally fluorapatite,
Seppo Karvinen   +3 more
doaj   +1 more source

MAGNETITE DEPOSITS OF THE TOMTOR (ONKUCHAKH AREA) AND KOVDOR PLUTONS: A PROBLEM OF ORE PRECARBONATITES [PDF]

open access: yesМинералогия, 2018
The comparative characteristics of magnetite deposits of the Kovdor (camaphorite deposit) and Tomtor (Onkuchakh area) plutons, which were formed during the carbonatite stage of the formation of the plutons and can be classified «ore precarbonatites», is ...
A.V. Lapin   +3 more
doaj  

Carbonatites of India [PDF]

open access: yesJournal 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,
openaire   +1 more source

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