S. Shnyukov1, Dr. Sci. (Geol.), Associate Professor, E-mail: firstname.lastname@example.org,
I. Lazareva1, Cand. Sci. (Geol.), Associate Prof., E-mail: email@example.com,
Yu. Nykanorova1, Engineer, E-mail: firstname.lastname@example.org
FENITE HALOS OF LINEAR CARBONATITE MASSIFS:
IDENTIFICATION CRITERIA AND DETERMINATION OF GEOLOGICAL STRUCTURE
1Institute of Geology, Taras Schevchenko National University of Kyiv 90 Vasylkivska Str., Kyiv, 03022 Ukraine
In this paper, there have been contrasted the morphological features of fenite halos associated with the two types of carbonatite massifs: linear – Chernigovka, Dubravinka, Penchenga (Ukrainian Shield, Voronezh crystalline massif and Yenisei Ridge, respectively) and central – Alno, cape Turiy (Baltic Shield). It has been found that, in contrast to the isometric fenite halos of the central type massifs, fenite halos of linear massifs generally show irregular thickness (or even rare occurrence) and morphological asymmetry best expressed in the case of the flat-dipping of carbonatite bodies. There have been determined the geochemical features of the most common accessory minerals (zircon, apatite, sphene) from zonal fenite halos of linear type massifs. The identified distribution patterns for trace elements in accessory zircons from the fenite halo rocks of Chernigovka carbonatite massif may be applied as a criterion when classifying metasomatic rocks as fenites. The distribution features of trace elements in apatites and sphenes from fenite halo rocks are the key to identifying the contrast types of host rocks, as well as estimating their transformation level, and they clearly illustrate the composition convergence of the newly formed accessory minerals. The results obtained provide motivation for the use of data on trace elements composition of the most common accessory minerals from fenite halos in a complex of forecasting and prospecting criteria. These data are essential in describing the morphology of the halos, revealing and mapping their zonation, and optimizing the fenite nomenclature.
Keywords: carbonatites, fenitization, trace elements, accessory minerals, zircon, apatite, sphene, Ukrainian Shield, Baltic Shield, Yenisei Ridge, Voronezh crystalline massif.
1. Bagdasarov Yu.A., (1979). Linear-fractured carbonatite bodies – the new subformation of ultrabasic-alkaline carbonatite complexes. Reports of the USSR Academy of Sciences, 248, 2, 412-415 (In Russian).
2. Bagdasarov Yu.A., Voronovskiy S.N., Ovchinnikova L.V., (1985). Geological position features and radiological age of the new carbonatites occurrence in the KMA Region. Reports of the USSR Academy of Sciences, 282, 2, 404-408 (In Russian).
3. Bocharov V.L., Frolov S.M., (1992). Apatite-bearing carbonatites of the KMA region. Voronezh: The Peter's Square, 123 p. (In Russian).
4. Vrublevskiy V.V., Pokrovskiy B.G., Zhuravlev D.Z., Anoshin G.N., (2003). The composition and age of the Penchenga linear carbonatite complex, Yenisei Ridge. Petrology, 11, 2, 145-163 (In Russian).
5. Glevasskiy E.B., Krivdik S.G., (1981). Precambrian carbonatite complex, Pre-Azov Region. Kiev, The scientific thought, 227 p. (In Russian).
6. Dunaev V.A., (2006). Geological structure and genesis features of Dubravinka massif alkaline rocks and carbonatites (KMA). News of higher educational institutions. Geology and exploration, 5, 30-33 (In Russian).
7. Evdokimov M.D., (1982). Fenites of the Turiy alkaline complex of the Kola peninsula. Leningrad, Publishing House of Leningrad University, 248 p. (In Russian).
8. Lazareva I.I., (2006). The geochemistry of Suschano-Perzhanska zone metasomatites formation processes and their most common accessory minerals (The Ukrainian Shield). Ph. D. Thesis. Kyiv, 22 p. (In Ukrainian).
9. Lapin A.V., Ploshko V.V., Malyshev A.A., (1987). The carbonatites of the Tatarska deep-seated fault zone in the Yenisei Ridge. The geology of ore deposits, 1, 30-45 (In Russian).
10. Nykanorova Yu.Ye., Osypenko V.Yu., (2015). Formation features of linear carbonatite massifs metasomatic halos of Ukrainian Shield, Yenisei Ridge and Voronezh crystalline massif. Modern Science, 1, 133-141. (In Russian).
11. Samoylov V.S., (1984). The geochemistry of carbonatites. Moscow, The science, 193 p. (In Russian).
12. Sergeev A.S., (1967). Fenites of the ultrabasic and alkaline rocks complex. Leningrad, Publishing House of Leningrad University, 164 p. (In Russian).
13. Khodorovskiy M.S., Mineralogical-geochemical characteristic of uraniumbearing garnet-diopside type apogranitic albitites of Ukrainian Shield central part. Ph.D. Thesis. Kiev, 20 p. (In Russian).
14. Shnyukov S.E., (1983). Fenitization process features of Chernigovka carbonatite complex of the West Pre-Azov Region. The geological journal, 43, 4, 52-61. (In Russian).
15. Shnyukov S.E., (1988). Apatite, zircon and sphene from fenites associated with carbonatites, and alkaline metasomatic rocks of Ukrainian Shield diaphthoresis zones as petrogenetic and geochemical indicators. Ph.D. Thesis. Lvov, 25 p. (In Russian).
16. Shnyukov S.E., (2003). The admixture elements geochemistry in the most common accessory minerals. Dr. Sc. Thesis. Kiev, 35 p. (in Russian).
17. Shnyukov S.E., Lazareva I.I., (2003). Admixture elements of associated zircons, apatites, and sphenes as the criteria of the formation type and metasomatic zonation. The geological journal, 2, 107-112 (In Russian).
18. Shnyukov S.E., Scherbina R.N., (1984). Desilicated rocks of the Chernigovska zone. Reports of the Ukrainian SSR Academy of Sciences, B series, 2, 28-30 (In Russian).
19. Scherbak N.P., Zagnitko V.N., Artemenko G.V., Bartnitskiy E.N., (1995). Geochronology of large geological events in Priazovskiy block of USh. Geochemistry and Ore Formation, 21, 112-129 (In Russian).
20. Andersson M., Malehmir A., Troll V.R., Dehghannejad M., Juhlin C., et al., (2013). Carbonatite ring-complexes explained by caldera-style volcanism. Scientific Reports, 3, 1-9.
21. Kogarko L.N., Kononova V.A., Orlova M.P., Woolley A.R., (1995). Alkaline rocks and carbonatites of the world. Part 2 – Former USSR. London: Chapman & Hall, 226 p.
22. Kresten P., (1976). A magnetometric survey of the Alnö Complex. Geol. Fören. Stockh. Förh, 98, 361-362.
23. Morogan V., (1989). Mass transfer and REE mobility during fenitization at Alnö, Sweden. Contrib. Mineral. Petrol., 103, 25–34.
24. Vuorinen J.H., (2005). The Alnö alkaline and carbonatitic complex, east central Sweden – a petrogenetic study. Dr. Sc. Thesis. Stockholm, University of Stockholm, 130 p.