Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

Mary K. Kumar ¹, D. Veera Baskar ², Mithilesh Sharma ³, T. Chabria ⁴, R. Dhanar Raju ³

Affiliations
1 Atomic Minerals Division, Department of Atomic Energy, Bangalore - 560 072, IN
2 Atomic Minerals Division, Department of Atomic Energy, Nagpur - 440 001, IN
3 Atomic Minerals Division, Department of Atomic Energy, Bangalore - 560 072, IN
4 Atomic Minerals Division, Department of Atomic Energy, Hyderabad - 500 016, IN

Abstract

Sulphur-isotopic dataon fifteen samples of baryte from the quartz-baryte rock occurring along a shear zone east of the Elagiri Syenite pluton at Andiyappanur, Tamil Nadu have shown a narrow range of +5.1‰ to +9.5‰, with an average of +6.70‰, for δ³⁴S_CDT. The data, in conjunction with the field and petromineralogical characteristics, indicate hydrothermal-type mineralisation of baryte. Association of relatively earlier formed sulphides like pyrite, molybdenite and galena, and later formed sulphates like baryte and jarosite in this quartz-baryte rock is attributed to dual behaviour of sulphur in the magmatichydrothermal system, with formation of sulphides at depth under reducing conditions and of sulphates in the shallower oxidised zones.

Keywords

Baryte, Geochemistry, Andiyappanur, Tamil Nadu.

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Mithilesh Sharma ¹, T. P. S. Rawat ¹, Y. C. Sharma ², B. M. Swarnkar ¹, Jagmer Singh ³

Affiliations
1 Department of Atomic Energy, AMD, New Delhi - 110 066, IN
2 40312, Chand Nagar, New Delhi - 1 10 018, IN
3 407, Pacific Apartment, X/39, Dwarka, New Delhi - 110 045, IN

Abstract

Ground radiometric survey carried out in the early Tertiary Dagshai-Kasauli Formations in the northwestern foothill Himalaya has led to the discovery of uranium mineralised sandstone bands extending for about (a) 500 m, with 5-10 m width, at Tarol, 8 km southwest of Solan and (b) 250 m, with 4-7 m width, at Maltu, 6.5 km southwest of Solan, in the Solan district of Himachal Pradesh. Grab samples from (a) Tarol assayed up to 1.41% eU₃O₈, 1.65% U₃O₈ (β/γ) and <0.005% Tho₂ and (b) Maltu assayed up to 0.24% eU₃O₈, 0.28% U₃O₈ (β/γ) and 2. In both the localities, majority of the samples show disequilibrium in favour of parent (uranium). Uraninite and uranophane are the main uranium minerals, which occur in close association with disseminated pellets of organic matter.

Keywords

Economic Geology, U-Mineralisation, Sandstone Type, Tertiary, Dharamsala, Solan, Himachal Pradesh.

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