Yttrium-Europium-Erbium Geochemistry of Granitic Soils of Kunkuri Area, Raigarh District, Madhya Pradesh, India

The duricrust and the soils derived from the Precambrian granitic rocks of Kunkuri area in Raigarh district, Madhya Pradesh, contain anomalous concentratioIis of rare earth and yttrium minerals. The polymineral table concentrates obtained from the granitic soil contain xenotime, monazite, zircon, Hmenite and rutile. Chemical analyses of table concentrate indicate values up to 3.08% Y ₂0₃.0.30% Er₂0₃ and 0.0286% EU₂0₃ in the ratio of 10 : 1 : 0.1. Corresponding data on table concentrates from the source granitic rocks also demonstrate a similar form in Y ₂0₃ : Er₂0₃ : EU₂0₃' Y/Er ratio is 10. which is similar to the average granites, while Er/Eu ratio of 10 is anomalously high, being 4 times the average for granitic rocks. Since the REE and Y·bearing minerals are radioactive and contribute to a major part of the radioactivity in soHI alluvial deposits of the areas investigated, aeroradiometric surveys fonowed by ground radiometric checkings, preferably along 2nd to 5th order streams in the adjoining areas, are recommended.