U-Rich Pyrochlore from Sevathur Carbonatites, Tamil Nadu

Authors

  • Shrinivas G. Viladkar
     Carbonatite Research centre, Amba Dongar, Kadipani District, Baroda - 390 117
  • U. Bismayer
     Mineralogisch-Petrographisches Institute, Uni Hamburg, Hamburg

Keywords:

Carbonatites, Pyrochlore, Uranium, Tamil Nadu.

Abstract

In Sevathur pyrochlore occurs mainly in rauhaugite. All analysed pyrochlore grains are rich in UO2. Majority of pyrochlores show alteration to various degrees and maximum alteration is noticed in ones collected from the weathered soil around carbonatite outcrops. There is significant leaching of Ca and Na leading to A-site vacancy and gain in Ba (5 to 7%) and Sr. UO2 content, though show variation is present in all analysed grains. Elements like U and Th can be incorporated in mineral structures showing alpha and beta radiation. This may initiate a process of metamictization. It is reasonable to assume that these pyrochlore grains are metamict.

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Issue

Volume 83, Issue 2, February 2014

Section

Research Articles

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Published

2014-02-12

How to Cite

Viladkar, S. G., & Bismayer, U. (2014). U-Rich Pyrochlore from Sevathur Carbonatites, Tamil Nadu. Journal of Geological Society of India, 83(2), 175–182. Retrieved from http://www.geosocindia.com/index.php/jgsi/article/view/56882

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