Advertisement

Doklady Earth Sciences

, Volume 483, Issue 2, pp 1510–1514 | Cite as

First Data on the Isotopic Age of Zircons from Rocks of the Roseta Ultramafic Massif, Southern Margin of the São Francisco Craton (Brazil)

  • F. P. LesnovEmail author
  • M. A. P. Pinheiro
  • S. A. Sergeev
GEOCHEMISTRY
  • 14 Downloads

Abstract

The results of isotope U–Pb dating of zircons from lherzolite and vein olivine orthopyroxenite composing the Roseta ultramafic massif are presented. The zircons differ in their morphological, optical, and geochemical properties and in their age. Lherzolite samples that are almost deprived of cathodoluminescence are represented by two age clusters 788 ± 15 and 638.2 ± 5.4 Ma. The zircons from the first cluster are relict. A later event recorded in the zircons from the second cluster was manifested in an intense metamict mineral transformation. The age of the zircons from vein olivine orthopyroxenite conforms to 608.9 ± 3.4 Ma. These zircons are considered to be syngenetic; therefore, their age is determined by the time of crystallization of olivine orthopyroxenites.

Notes

ACKNOWLEDGMENTS

This work was performed at Sobolev Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of Sciences (Novosibirsk, Russia) and was supported by the Brazilian National Council for Scientific and Technical Development (CNPq), project no. 206612 / 2014-1.

REFERENCES

  1. 1.
    F. P. Lesnov, Petrology of Polygenic Mafic-Ultramafic Massifs of East-Sakhalin Ophiolitic Association (GEO, Novosibirsk, 2015) [in Russian].Google Scholar
  2. 2.
    M. A. P. Pinheiro and F. P. Lesnov, in Metallogeny of Ancient and Modern Oceans–2016. From Mineral Genesis to Deposits (Inst. Mineral. Ural Branch Russ. Acad. Sci., Miass, 2016), pp. 260–263 [in Russian].Google Scholar
  3. 3.
    F. F. M. Almeida, Rev. Bras. Geocienc. 7, 349–364 (1977).Google Scholar
  4. 4.
    B. B. Brito Neves, R. A. Fuck, and M. M. Pimentel, Braz. J. Geol. 44, 493–518 (2014).CrossRefGoogle Scholar
  5. 5.
    M. C. Campos Neto, M. A. S. Basei, J. V. Assis, et al., J. South Am. Earth Sci. 32, 393–406 (2011).CrossRefGoogle Scholar
  6. 6.
    F. V. P. Paciullo, A. Ribeiro, and R. A. J. Trouw, in Geologia e Recursos Minerals do Sudeste Mineiro, Projeto Sul de Minas-Etapa I (Companhia Mineradora de Minas Gerais, Belo Horizonte, 2003), Vol. 1, pp. 84–119.Google Scholar
  7. 7.
    S. Schuth, V. I. Gornyy, J. Berndt, et al., Int. J. Geosci. 3, 289–296 (2012).CrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2018

Authors and Affiliations

  • F. P. Lesnov
    • 1
    Email author
  • M. A. P. Pinheiro
    • 2
  • S. A. Sergeev
    • 3
  1. 1.Sobolev Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of SciencesNovosibirskRussia
  2. 2.Geological Survey of BrazilBelo HorizonteBrazil
  3. 3.Karpinskii Russian Geological Research Institute St. PetersburgRussia

Personalised recommendations