Chemical microprobe Th-U-Pb age dating of monazite from rare-metal pegmatites of the Burpala massif (North Baikal)

Cover Page

Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

The chemical composition and zoning of monazite from a dike of rare-metal pegmatites of the Britholite zone of the Burpala massif (Northern Baikal region) was studied by electron probe microanalysis (EPMA). It has been established that monazites are represented by Ce and La varieties. Grains of monazite-(Ce) are characterized by an increased concentration of Nd2O3 and ThO2 compared to monazite-(La). The weighted average age for monazites, determined by the U-Th-Pb CHIME method, was 251±31 Ma. The age calculated by the isochrone method corresponds to 273±69 Ma. The obtained age values of monazite indicate that the pegmatites of the Britholite zone were intruded after the pegmatites of the northwestern area and suggest the existence of several stages in the formation of rare-metal pegmatites in the massif.

Full Text

Restricted Access

About the authors

A. V. Spivak

D.S. KorzhinskyInstitute of Experimental Mineralogy, Russian Academy of Sciences

Author for correspondence.
Email: spivak@iem.ac.ru
Russian Federation, Chernogolovka

I. A. Sotnikova

A. P. Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences

Email: spivak@iem.ac.ru
Russian Federation, Irkutsk

A. A. Viryus

D.S. KorzhinskyInstitute of Experimental Mineralogy, Russian Academy of Sciences

Email: spivak@iem.ac.ru
Russian Federation, Chernogolovka

M. I. Kuzmin

A. P. Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences

Email: spivak@iem.ac.ru

Academician of the RAS

Russian Federation, Irkutsk

E. S. Zakharchenko

D.S. KorzhinskyInstitute of Experimental Mineralogy, Russian Academy of Sciences

Email: spivak@iem.ac.ru
Russian Federation, Chernogolovka

T. B. Kolotilina

A. P. Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences

Email: spivak@iem.ac.ru
Russian Federation, Irkutsk

N. V. Alymova

A. P. Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences

Email: spivak@iem.ac.ru
Russian Federation, Irkutsk

References

  1. Vladykin N.V, Sotnikova I. A. Geoscience Frontiers Petrology, geochemistry and source characteristics of the Burpala alkaline massif, North Baikal // Geosci. Front. 8 (2017) 711–719. https://doi.org/10.1016/j.gsf.2016.04.006.
  2. Котов А.Б., Владыкин Н. В., Ярмолюк В. В., Сальникова Е. Б., Сотникова И. А., Яковлева С. З. Пермский возраст Бурпалинского щелочного массива (Северное Прибайкалье): геодинамические следствия // ДАН. 453 (2013) 295–299. https://doi.org/10.7868/s0869565213330165.
  3. Vladykin N.V., Sotnikova I. A., Kotov A. B., Yarmolyuk V. V., Sal’nikova E.B., Yakovleva S. Z. Structure, age, and ore potential of the Burpala rare-metal alkaline massif, northern Baikal region // Geol. Ore Depos. 56 (2014) 239–256. https://doi.org/10.1134/S1075701514040060.
  4. Сотникова И. А. Минералого-геохимические особенности редкометальных щелочных пород Северного Прибайкалья / Автореф. дис. канд.геол.-мин. наук. Иркутск: ИГХ РАН, 2009.
  5. Clavier N., Podor R., Dacheux N. Crystal chemistry of the monazite structure, J. Eur. Ceram. Soc. 31 (2011) 941–976. https://doi.org/10.1016/j.jeurceramsoc.2010.12.019.
  6. Williams M.L., Jercinovic M. J., Hetherington C. J. Microprobe monazite geochronology: Understanding geologic processes by integrating composition and chronology // Annu. Rev. Earth Planet. Sci. 35 (2007) 137–175. https://doi.org/10.1146/annurev.earth.35.031306.140228.
  7. Suzuki K., Adachi M., Kajizuka I. Electron microprobe observations of Pb diffusion in metamorphosed detrital monazites // Earth Planet. Sci. Lett. 128 (1994) 391–405. 10.1139/e90-152' target='_blank'>https://doi.org/doi: 10.1139/e90-152.
  8. Montel J., Foret S., Veschambre M., Nicollet C., Provost A. CHEMICAL Electron microprobe dating of monazite, 1 (1996).
  9. Parrish R. U-Pb dating of monazite and its application to geological problems // Can. J. Earth Sci. 24 (1990) 1431–1450. 10.1139/e90-152' target='_blank'>https://doi.org/doi: 10.1139/e90-152.
  10. Meldrum A., Boatner L. A., Weber W. J., Ewing R. C. Radiation damage in zircon and monazite // Geochim. Cosmochim. Acta. 62 (1998) 2509–2520.
  11. Belyanin D.K., Karmanov N. S., Airiyants E. V., Zhmodik S. M. The Application of Scanning Electron Microscopy Using Energy- and Wavelength Dispersive Spectrometers for Chemical Dating of Uranium Mineralization on the Example of Carbonaceous Shales of the Dabanzhalga Suite (East Sayan) // Geodyn. Tectonophys. 13 (2022) 1–7. https://doi.org/10.5800/GT-2022-13-2s-0604.
  12. Ludwig K.R. ISOPLOT/ A geochronological toolkit for Microsoft Excel. Berkley Geochronology Center Sp. Publ., (1999) 1a. 49.
  13. Sotnikova I.A., Alymova N. V., Scherbakov Y. D. Mineralogical and Geochemical Features of Apatite-Fluorite Rocks of the Burpala Massif in the Northern Baikal Region // Geodyn. Tectonophys. 13 (2022) 1–10. https://doi.org/10.5800/GT-2022-13-4-0657.

Supplementary files

Supplementary Files
Action
1. JATS XML
Download
2. Fig. 1. Schematic geological map of the Burpalinsky massif. 1 – Quaternary deposits; 2 – sandstones, siltstones of the Kholodninsk formation; 3 – hornstones; 4 – shonkinites; 5 – nepheline syenites; 6 – striped trachytoid syenites; 7 – quartz syenites; 8 – Mariupol; 9 – foyaites; 10 – rare metal pegmatites; 11 – apatite-fluorite vein; 12 – carbonatites; 13 – alkaline granites; 14 – sampling site for geochronological Th-U‒Pb studies on monazite (1–Drill 310/9); 15 - sampling sites for U-Pb geochronological studies on zircon (2 – Drill 305/10 sample, 3 – Drill 313/10 sample [2,3]).

Download (939KB)
Indexing metadata
3. Fig. 2. BSE images of monazite grains of sample 310-9 (in reflected electrons) with the designation of the analysis points (digits are the sequence number of the analysis).

Download (425KB)
Indexing metadata
4. Fig. 3. Image of BSE (in reflected electrons). Inclusions of monazite and other minerals in apatite grains from rare metal pegmatites of the central part of the Burpalinsky massif. (a) – the main grain of apatite with inclusions of monazite; Ce-bastnesite, amphibole, albite with inclusion of zircon; (b) – grain of apatite with inclusions of monazite, amphibole, K-feldspar, albite; (c) – monazite in association with Ce-bastnesite, fluorite and quartz in apatite; (d) – monazite in apatite in association with carbonesite, fluorite, zircon and quartz. Designations: Ab – albite, Amp – amphibole, Ap – apatite, Bsn-Ce – bastnesite-(Ce), Flr – fluorite, Kfs– K- feldspar, Mnz – monazite, Qz – quartz, Zrn – zircon.

Download (429KB)
Indexing metadata
5. Fig. 4. The spread of point ages relative to the weighted average value of the age of the studied monocytes; item n. a. – the sequence number of the analysis corresponding to Table 4 (SQUAW = 2.2; the error was calculated according to the 2σ criterion).

Download (112KB)
Indexing metadata
6. Fig. 5. The ThO2*‒PbO isochron, constructed by the CHIME method, based on the results of the analysis of monocytes by the EZRS method (SQUAW = 1; the error is calculated by 2σ-criterion).

Download (126KB)
Indexing metadata

Copyright (c) 2024 Russian Academy of Sciences