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Date submitted2022-08-22
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Date accepted2023-02-02
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Date published2023-08-28
Wodginite as an indicator mineral of tantalum-bearing pegmatites and granites
- Authors:
- Viktor I. Alekseev
In the composition of tantalum-niobates, the tin-bearing wodginite group minerals (WGM) were found: wod-ginite, titanowodginite, ferrowodginite, ferrotitanowodginite, lithiowodginite, tantalowodginite, “wolframowodginite”. We reviewed the worldwide research on WGM and created a database of 698 analyses from 55 sources including the author's data. WGM are associated with Li-F pegmatites and Li-F granites. Wodginite is the most prevalent mineral, occurring in 86.6 % of pegmatites and 78.3 % of granites. The occurrence of WGM in granites and pegmatites differs. For instance, titanowodginite and “wolframowodginite” occur three times more frequently in granites than in pegmatites, whereas lithiowodginite and tantalowodginite do not appear in granites at all. The difference between WGM in granites and pegmatites is in finer grain size, higher content of Sn, Nb, Ti, W, and Sc; lower content of Fe 3+ , Ta, Zr, Hf; higher ratio of Mn/(Mn + Fe); and lower ratio of Zr/Hf. The evolutionary series of WGM in pegmatites are as follows: ferrowodginite → ferrotitanowodginite → titanowodginite → “wolframowodginite” → wodginite → tantalowodginite; in granites: ferrowodginite → ferrotitanowodginite → “wolframowodginite” → wodginite → titanowodginite. WGM can serve as indicators of tantalum-bearing pegmatites and granites. In Russia the promising sources of tantalum are deposits of the Far Eastern belt of Li-F granites containing wodginite.
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Date submitted2022-02-26
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Date accepted2022-04-27
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Date published2022-07-26
Type intrusive series of the Far East belt of lithium-fluoric granites and its ore content
- Authors:
- Viktor I. Alekseev
The evolution and ore content of granitoid magmatism in the Far East belt of lithium-fluoric granites lying in the Russian sector of the Pacific ore belt have been studied. Correlation of intrusive series in the Novosibirsk-Chukotka, Yana-Kolyma and Sikhote-Alin granitoid provinces of the studied region allowed to establish the unity of composition, evolution, and ore content of the Late Mesozoic granitoid magmatism. On this basis, a model of the type potentially ore-bearing intrusive series of the Far East belt of lithium-fluoric granites has been developed: complexes of diorite-granodiorite and granite formations → complexes of monzonite-syenite and granite-granosyenite formations → complexes of leucogranite and alaskite formations → complexes of rare-metal lithium-fluoric granite formation. The main petrological trend in granitoid evolution is increasing silicic acidity, alkalinity, and rare-metal-tin specialization along with decreasing size and number of intrusions. At the end of the intrusive series, small complexes of rare-metal lithium-fluoric granites form. The main metallogenic trend in granitoid evolution is an increasing ore-generating potential of intrusive complexes with their growing differentiation. Ore-bearing rare-metal-granite magmatism of the Russian Far East developed in the Late Cretaceous and determined the formation of large tungsten-tin deposits with associated rare metals: Ta, Nb, Li, Cs, Rb, In in areas with completed intrusive series. Incompleteness of granitoid series of the Pacific ore belt should be considered as a potential sign of blind rare-metal-tin mineralization. The Far East belt of lithium-fluoric granites extends to the Chinese and Alaskan sectors of the Pacific belt, which allows the model of the type ore-bearing intrusive series to be used in the territories adjacent to Russia.
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Date submitted2020-08-03
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Date accepted2020-12-13
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Date published2021-06-24
Tectonic and magmatic factors of Li-F granites localization of the East of Russia
- Authors:
- Viktor I. Alekseev
We have investigated tectonic and magmatic factors of Li-F granites localization of the East of Russia. The study is based on the ideas of Far Eastern geologists about the deep structures of intraplate activity. A model of a source structure with mantle heat sources and ore-forming magmatic complexes was used. We carried out a special metallogenic analysis of the East of Russia as applied to the rare metal-tin-bearing formation of subalkaline leucogranites, including Li-F ones. Source structures are the main factor in the tectonic and magmatic development of the East of Russia, localization of ore-forming granites and the formation of rare-metal-tin ore regions. On deep layers of source structures there are areas of the mantle and earth's crust decompaction, heat, magmas and fluids sources, as well as granitoid cryptobatholiths. Relatively large massifs of leucogranites, small intrusions of tin monzonitoids and Li-F granites are concentrated near the modern surface. The source structures correspond to the rank of the ore region. The source structures in the South of the region are: Badzhalskaya, Miao-Chanskaya, Ippato-Merekskaya, Hogdu-Lianchlinskaya, Arminskaya, etc.; in the North: Pevekskaya, Kuiviveem-Pyrkakayskaya, Kuekvun-Ekiatapskaya, Iultinskaya, Telekayskaya, Central Polousnaya, Omsukchanskaya, etc. Three types of ore regions have been identified according to the degree of source structures and Li-F granites erosion. We have also outlined the patterns of source structures evolution and their place in the geological history of ore-bearing granites. A classification of source structures and its comparison with the classifications of regional intrusives and metallogenic subdivisions are proposed. It has been established that, despite the diversity of tectonic, geological and petrological settings in the East of Russia, the intrusions of Li-F granites are regulated by the same tectonic and magmatic factors. The tectonic and magmatic factors of Li-F granites localization in the East of Russia are identified and classified as geophysical, orogenic, geoblock, magmatic, metasomatic and disjunctive.
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Date submitted2019-07-11
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Date accepted2019-09-11
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Date published2020-04-24
Research of lithium sorption by KU-2-8 cation exchanger from model solutions simulating geothermal fluids in the dynamic mode
- Authors:
- Tatiana P. Belova
- Tatiana I. Ratchina
The extraction of chemical compounds from hydromineral raw materials is currently a promising objective. The geothermal deposits in the Kamchatka Territory should be considered as possible sources of lithium, boron and other chemical compounds. Their economic efficiency is justified by the complexity of the use of resources of geothermal fluids. The article presents data obtained as a result of experimental studies of lithium sorption by KU-2-8 cation exchanger from model solutions that simulate geothermal fluids in the dynamic mode. It was shown that in the first phase of sorption, ion exchange results in the absorption of lithium and sodium ions by the hydrogen form of cation exchanger up to the degree of cation exchanger saturation by 78 %. After that, the displacement of lithium ions by sodium ions is observed. The intermediate solutions were obtained in which the molar ratio of Li/Na is 80 times higher than in the initial solution. To separate sodium and lithium, it is proposed to use the lithium form of cation exchanger obtained using a portion of lithium chloride concentrate. The separation occurs due to the displacement of lithium ions by sodium ions. The effluent has a molar ratio of Li/Na = 10.4. The regeneration is carried out with 1 n hydrochloric acid, while the concentration coefficient of sodium chloride equals three.