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

M. N. Praveen ¹, Biswajit Ghosh ¹, H. S. Shrivastava ¹, M. L. Dora ², L. D. Gaikwad ¹

Affiliations
1 Geological Survey of India, E-5 Arera Colony, Bhopal - 462 016, IN
2 Geological Survey of India, Seminary Hills, Nagpur - 440 006, IN

Abstract

Sulphide mineralisation and syn-Volcanic hydrothermal alteration in the Betul Belt is associated with submarine bimodal volcanism. Felsic volcaniclastics form the favourable host rocks in most areas. Alteration zones have been metamorphosed to middle to upper-Amphibolite facies giving rise to various metamorphic mineral assemblages. Based on metal ratios, mineralisation can be classified into Zn-Cu and Zn-Pb-Cu types. The difference between the two types might be related to the composition of the footwall volcanics. Zn-Cu types are in close proximity to mafic volcanics towards their footwall side whereas, Zn-Pb-Cu types occur in areas dominated by felsic volcanics with little mafic volcanics towards the footwall. The sub-Parallel sheet like nature of the ore bodies and strata-Bound alteration might be related to the permeable nature of the host volcaniclastics.

Keywords

Sulphide Mineralisation, Classification, Hydrothermal Alteration, Subsea-Floor Replacement, Betul Belt, Central India.

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Biswajit Ghosh ¹, M. N. Praveen ², H. S. Shrivastava ²

Affiliations
1 Geological Survey of India, E-5 Arera Colony, Bhopal - 462 016
2 Geological Survey of India, E-5 Arera Colony, Bhopal - 462 016, IN

Abstract

Gahnite Chemistry from metamorphosed Zn-Pb-Cu sulphide occurrences of Betul Belt, Central India has been presented here. Gahnites of this Belt are suggested to be a product of desulphidation of sphalerite during metamorphism. Although the very presence of zincian spinels in rocks may appear to constitute an exploration guide for metamorphosed massive sulphide (MMS) deposits, spinels that are likely to be spatially associated with sulphides appear to have characteristic Zn-rich, Mg-poor compositions.

Keywords

Gahnite Chemistry, Zn-Pb-Cu-Deposits, Genetic Implications, Betul Belt, Central India.

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