Khmilnyk Ore Occurrence of Potassium-Uranium Rock Association: Mineralogy, Geochemistry, Formation Time (the Ukrainian Shield)

UDC 553.411.071 (477)

https://doi.org/10.15407/mineraljournal.37.04.106

S.M. Bondarenko, L.M. Stepanyuk, Z.V. Karly, V.O. Syomka, N.A. Donskoy, L.V. Syomka

M.Р. Semenenko Institute of Geochemistry, Mineralogy and Ore Formation of the NAS of Ukraine

34, Acad. Palladina Pr., Kyiv-142, Ukraine, 03680

Е-mail: sbond@igmof.gov.ua; stepanyuk@igmof.gov.ua; syomka@igmof.gov.ua; donick_gg@mail.ru

Khmilnyk Ore Occurrence of Potassium-Uranium Rock Association: Mineralogy, Geochemistry, Formation Time (the Ukrainian Shield)

Language: Ukrainian

Mineralogical journal 2015, 37 (4): 106-122

Abstract: Uranium concentration exceeding ten times the uranium average concentration in crystalline rocks of the Ukrainian Shield is established in aplite-pegmatoid two-feldspar granites and apo-pegmatoid silica-potassium metasomatites of the Khmilnyk ore occurrence. Uranium concentration in graphitic garnet-biotite gneisses is about two times more than the average concentration in crystalline rocks of the Ukrainian Shield; it is indicative for Zavallya uranium occurrence as well. Two main types of ore associations are identified. The first one is accessory mineralization in aplite-pegmatoid feldspathic granites; it consists of apatite, zircon, monazite and uraninite-I. The second one is a superimposed hydrothermal and metasomatitic mineralization in cataclastic zones of pegmatites and aplites of the uranium occurrence. It is represented by rare earth-thorium-uranium mineralization (zircon + monazite + uranitite + autunite), oxide one (ilmenite + anatase + rutile + iron hydroxides) and sulphide one (pyrrhotite + pyrite + chalcopyrite + galenite + molybdenite). It is determined that the earliest accessory uraninite-I is characterized by increased thorium content and occurs in aplite-pegmatoid granites. Uraninite-II with lower thorium content is a typical mineral of silica-potassium metasomatites. The TR-Th-U mineralization of the Khmilnyk ore occurrence is defined as potassium-uranium type, according to its mineralogical and geochemical features. This type is widespread within the Dniester-Bug and Ingulets megablocks of the Ukrainian Shield and interblock sutural zones.

Keywords: Khmilnyk ore occurrence, age, mineralogy, geochemistry, zircon, monazite, uraninite, autunite.

References:

1. Bondarenko, S.M., Karli, Z.V., Stepanyuk, L.M., Syomka, V.O., Dons’kij, M.O. and Syomka, L.V. (2014), Mіneral. Journ. (Ukraine), Kyiv, Vol. 36 No 4, pp. 107-121.
2. Bondarenko, S.M., Karli, Z.V., Stepanyuk, L.M., Syomka, V.O., Dons’kij, M.O. and Syomka, L.V. (2014), Geohіmіja ta rudoutvorennja, Kyiv, Vyp. 34, pp. 3-17.
3. Klochkov, V.M., Pastuhov, V.G. and Pashkevich, I.K. (1983), in Shcherbak, M.P. (ed.), Geologicheskaja karta kristallicheskogo osnovanija Ukrainskogo shhita m-ba 1 : 500000 s objasn. zap., Mingeo USSR, Centr. temat. eksp., Kyiv.
4. Egorov, Yu.P. and Tikhonenko, V.A. (1981), Himicheskie sostavy porod, regional’nye klarki i geokhimicheskie fony elementov Ukrainskogo shhita, Kyiv, 2 p.
5. Shcherbak, M.P., Zlobenko, V.G., Zhukov, G.V., Kotlovskaja, F.I., Polevaja, N.I., Komlev, L.V., Kovalenko, N.K., Nosok, G.M. and Pochtarenko, V.I. (1978), Katalog izotopnyh dat porod Ukrainskogo Shhita, Nauk. dumka, Kyiv, 224 p.
6. Stepanyuk, L.M., Ponomarenko, O.M., Petrichenko, K.V., Kurilo, S.І., Dovbush, T.І., Sergejev, S.A. and Rodіonov, M.V. (2015), Mіneral. Journ. (Ukraine), Kyiv, Vol. 37 No 3, pp. 51-66.
7. Syomka, V.O., Bondarenko, S.M., Patalaha, M.Je., Vashchenko, V.P. and Bondarenko, І.M. (2006), Mіneral. Journ. (Ukraine), Kyiv, Vol. 28 No 4, pp. 59-75.
8. Tsymbal, S.M., Dovgan’, R.M., Jentіn, V.A., Kryvdіk, S.G., Pavljuk, V.M. and Tsymbal, Yu.S. (2010), Geohіmіja ta rudoutvorennja, Kyiv, Vyp. 28, pp. 28-48.
9. Elming, S.-Å., Shumlyanskyy, L., Kravchenko, S., Layer, P. and Söderlund, U. (2010), Precambr. Res., Vol. 178, pp. 119-135.
10. Krough, T.E. (1973), Geochim. et cosmochim. acta, Vol. 37 No 3, pp. 485-494.
11. Ludwig, K.R. (1989), U.S. Geol. Surv. Open-File Rept., Vol. 542 No 88, р. 40.
12. Ludwig, K.R. (1990), U.S. Geol. Surv. Open-File Rept., Vol. 557 No 88, р. 38.

English