Geochemistry of Spinifex-Textured Peridotitic Komatiites from Ghatti Hosahalli, Karnataka, Indi

Spinifex-textured peridotitic komatiites (STPK) of Ghatti Hosahalli have low CaO/Al₂O₃ ratio (< 1), low TiO₂, K₂O and high MgO. These STPK have comparable Ni and Co contents with those of the Australian and Canadian shields. These characters support the view that the spinifex-texture observed in these rocks is primary and not the result of later metamorphism. The Al₂O₃/TiO₂ ratios are comparable to those of Chondrites indicating that the STPK are products of partial melting of the Archaean mantle. The STPK of Ghatti Hosahalli arc overlain by exhalative chemical precipitates and argillaceous metamorphosed sediments like bedded-barytes, fuchsite-quartzites and kyanite-mica schists. It is suggested that Ghatti Hosahalli band is a relic of an early Archaean greenstone belt.