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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Viladkar, S.G., Bismayer, U. U-rich pyrochlore from sevathur carbonatites, Tamil Nadu. J Geol Soc India 83, 175–182 (2014). https://doi.org/10.1007/s12594-014-0030-5
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DOI: https://doi.org/10.1007/s12594-014-0030-5