The Vuoriyarvi Devonian carbonatite–ijolite–pyroxenite–olivinite complex comprises several carbonatite fields: Neske Vara, Tukhta-Vara, and Petyayan-Vara. most common carbonatites in the Tukhta-Vara Neske-Vara fields are calciocarbonatites, which host P, Fe, Nb, Ta deposits. This paper focuses on Petyayan-Vara field, primary magmatic magnesian. least altered magnesiocarbonatites composed of dolomite with burbankite rich REE (up to 2.0 wt. %), Sr 1.2 Ba 0.8 %). These underwent stages...

This article is devoted to the geology of titanium-rich varieties Petyayan-Vara rare-earth dolomitic carbonatites in Vuoriyarvi, Northwest Russia. Analogues these are present many carbonatite complexes. The aim this study was investigate behavior high field strength elements during late stages formation. We conducted a multilateral titanium- and niobium-bearing minerals, including petrographic study, Raman spectroscopy, microprobe determination chemical composition, electron backscatter...

The Vuoriyarvi Devonian alkaline–ultramafic complex (northwest Russia) contains magnesiocarbonatites with rare earth mineralization localized in the Petyayan-Vara area. High concentrations of elements are found two types these rocks: (a) ancylite-dominant ancylite–baryte–strontianite–calcite–quartz (±late Ca–Fe–Mg carbonates) ore assemblage, i.e., “ancylite ores”; (b) breccias a quartz–bastnäsite matrix carbonates), “bastnäsite ores.” We studied fluid inclusions quartz and late-stage...

The Precambrian rocks of the Keivy Terrane reveal five types carbonaceous matter (CM): Fine-grained, flaky, nest, vein, and spherulitic. These differ in their distribution character, carbon isotope composition, graphitization temperatures calculated by Raman spectra material (RSCM) geothermometry. Supracrustal contain extremely isotopically light (δ13CPDB = –43 ± 3‰) carbon. Presumably, its source was a methane–aqueous fluid. According to temperature calculations, this host strata underwent...

SUMMARY Electrically conductive minerals (e.g. graphite, pyrite, chalcopyrite and magnetite) occur in the various geological contexts. They might represent economic resources or serve as indicators of such resources. In addition, they can be sources contamination soil groundwater. Therefore, characterization rocks containing electrically inclusions is an important task many sectors science economy. We conducted laboratory measurements to study impact shape, composition, size passivation...

Abstract. Raman spectra of three natural carbonophosphates (sidorenkite, bonshtedtite, and bradleyite) with the general formula Na3MCO3PO4 (M is Mn, Fe, Mg) were studied compared. These showed from 21 to 24 vibrational bands, which two most intense (964±5 1074±3 cm−1) correspond υ1(P–O) υ1(C–O) modes. bands split into doublet peaks due occurrence isomorphic impurities. It was found that crystallographic orientation sample influences intensity bands. Most assigned same vibrations a regular...

This paper presents an example of comparing geochemical and mineralogical data by means the statistical analysis X-ray diffraction patterns chemical compositions bulk samples. The proposed methodology was tested on samples metasomatic rocks from two geologically different objects. Its application allows us to mathematically identify all main, secondary some accessory minerals, qualitatively estimate contents these as well assess their effect distribution petrogenic investigated trace...

This paper aims to develop a principle for selecting the most informative samples geological research from extensive collections of rock material. As tool this selection, we chose an original method statistical comparison X-ray powder diffraction (XRPD) and fluorescence (XRF) data using factor analysis (FA). A collection carbonatites aluminosilicate rocks Kontozero Devonian carbonatite paleovolcano complex (198 samples) is presented test our technique. The factors extracted during FA were...

Numerical comparison of mineralogical and geochemical data, which is required in a variety geological applications, challenging task, especially when analyzing extensive sample collections. Herein, we apply factor analysis (FA) to collection 198 diffraction patterns bulk rock samples from the Kontozero carbonatite complex. The information hidden X-ray powder (XRPD) data thereby squeezed down set two dozen variables represented by scores (FS). values these FSs show functional relationship...

The Vuoriyarvi massif is a Devonian multistage alkaline-ultrabasic carbonatite complex within the Kola alkaline province. Dolomite carbonatites of contain abundant rare-earth mineralization mainly represented by ancylite-(Ce) and bastnäsite-(Ce). Ancylite was previously shown to have probably formed in (ca. 365 Ma) during an early postmagmatic overprint. Previous geological observations revealed much later crystallization bastnäsite but not been able specify exact age mineralization. situ...

This study develops a method to estimate the redistribution of elements during several associated metasomatic processes simultaneously involved in formation geological complex. The is based on classical mass balancing using isocon analysis. proposed approach applicable if prerequisites indicate that (a) rocks inherited some components (x, y, etc.) from one earlier studied complex; (b) these have been transported by fluid; and (c) this saturated fluid has produced varieties rich x, etc. In...

Raman spectra of lucasite-(Ce), La-analogue lucasite, kassite and cafetite are significantly different. Most evident differences were revealed in the position bands corresponding to vibrational modes for assigned symmetrical v1(Ti-O) asymmetrical v3(O-Ti-O) stretching vibrations, as well determined by bending vibrations v4(transTiO6) vibrations. lucasite-(Ce) lucasite published first time. The presented data valuable identification group minerals using spectroscopy.

Abstract We investigated carbonatites and aluminosilicate rocks from the Kontozero Devonian carbonatite paleovolcano complex (198 samples). Some specific features complicate geological exploration of this object: a) are predominantly volcanic therefore exhibit small dimension mineral grains diversity their structural relationships; b) because breccias common in many parts complex, mostly inhomogeneous; c) belongs to alkaline-carbonatite formation, which is typically characterised by presence...

Генезис апокарбонатитовых титанистых метасоматитов редкоземельного рудопроявления Петяйян-вара (Вуориярви, Кольский регион) Исследовались титанистые апокарбонатитовые метасоматиты (титанистые карбонатиты), связанные с редкоземельными карбонатитами участка комплекса Вуориярви (Кольский регион).В настоящей работе на основании согласованных результатов минералогического и геохимического исследования обосновывается следующий механизм образования этих пород.До начала карбонатитогенеза из нижних...

The Sallanlatva massif belongs to the group of Paleozoic alkaline-ultrabasic complexes wide spread in Kola Region (the northwestern part Fennoscandian Shield). In central this massif, host ijolite and urtites contain calcite, ankerite, ankerite-dolomite siderite carbonatites. explosive processes that led formation carbonatite breccias calcite carbonatites occurred massife last stages magmatism. There are two types massif: (1) glimmerite-calciocarbonatite breccias, (2) siderite-dolomite...

Summary The work is based on interpretation of new data acquired by JSC MAGE in 2016 the northern part Kara Sea between Franz Josef Land and Severnaya Zemlya archipelagoes (Zemlya Nikolaya Vtorogo), including Ushakov Island volume 4000 LKM.

Abstract We applied factor analysis (FA) for statistical comparison of XRF and XRD data on 198 carbonatite aluminosilicate rock samples the Kontozero Devonian paleovolcano. This method helps to identify main, secondary, some accessory minerals, as well estimate approximate contents these minerals assess their contribution distribution major trace elements (Fomina et al., 2019). With view control purposes, qualitative semiquantitative diffraction were performed. Several dozen factors quickly...