Affiliation:
1. Institute of Geology — Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences
Abstract
The paper presents materials on the study of rare earth mineralization in rocks of the Shatak complex, which belongs to the Mashak formation (RF2). Numerous rare earth minerals have been discovered and characterized in detail in terrigenous rocks, metabasalts and rhyodacites: allanite-(Ce), monazite-(Ce), monazite-(La), monazite-(Nd), nioboeschinite-(Y), aeshinite-(Y) , talenite-(Nd), talenite-(Dy), synchysite-(Ce), Ce–La–Fe oxide, cerite and unidentified compounds: yttrium silicate, cerium silicate, Ce–Fe compound, as well as REE-containing minerals: epidote and fluorapatite. In the contact zone between metabasalts and quartz sandstones, oxyfluoride – (La, Ce) (OnFm)3 mineralization, represented by compounds of variable composition, forming an isomorphic series: trifluoride (La, Ce)F3 – oxyfluoride (La, Ce)OF, is described for the first time in the world literature –oxide (La, Ce)2O3.
It has been established that the determining factors in the formation of rare earth mineralization in the rocks of the Shatak complex are the conditions and nature of metamorphism and the chemistry of the mineral formation environment.
The species diversity of rare earth minerals and the peculiarities of their chemical composition make the Shatak volcanic-sedimentary complex a unique object for studying the processes of rare earth mineral formation in various petrotypes of rocks formed in a single geotectonic setting and united by common thermobaric parameters of metamorphism.
Reference44 articles.
1. Alekseev A.A., Timofeeva E.A. (2007). Redkozemel'no-fosfatnaya mineralizatsiya v metaterrigennykh tolshchakh rifeya Bashkirskogo megantiklinoriya [Rare-earth-phosphate mineralization in metaterrigenous strata of the Riphean Bashkir meganticlinorium]. Geological collection, 6, 251–257. (In Russian). http://ig.ufaras.ru/File/E2007/30_01_07.pdf
2. Becker Yu.R. (1960). Litologicheskie osobennosti oligomiktovykh porod devona almazonosnykh raionov Yuzhnogo Urala [Lithological features of Devonian oligomictic rocks in the diamondiferous regions of the Southern Urals]. Geology and minerals of the Urals and Turgay. L.: VSEGEI, 73–102. (In Russian).
3. Bulakh A.G. (1967). Rukovodstvo i tablitsy dlya rascheta formul mineralov [Guidelines and tables for calculating mineral formulas]. Moscow: Nedra, 141 p. (In Russian).
4. Kobyashev Yu.S., Nikandrov S.N., Valizer P.M. (2000). Mineraly Il'menskikh gor [Minerals of the Ilmensky mountains]. Miass: IGZ UB RAN, 119 p. (In Russian).
5. Kovalev S.G., Vysotsky S.I., Kovalev S.S. (2018). Model' obrazovaniya magmaticheskikh porod Shatakskogo kompleksa [Model of formation of igneous rocks of the Shatak complex]. Geologicheskiy vestnik, 2, 3–13. (In Russian). http://doi.org/10.31084/2619-0087/2018-2-1