The abundances of some trace-elements in the first-ever reported sample of spinifex-textured komatiite from Ghatti Hosahalli, Karnataka

摘要

The paper reports wavelength-dispersive x-ray fluorescence spectrometric data on the abundances of Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in the first-ever reported sample of spinifex-textured komatiite from India at Ghatti Hosahalli in Karnataka. With some exceptions, these abundances are similar to those reported for the spinifex-textured komatiite from the Barberton greenstone belt in South Africa. The values for some alteration-resistant element ratios — Ti/Zr, Ti/Y, Ti/Sc, Ti/V, Zr/Y, Zr/Sc, Sc/Y, V/Zr, and V/Sc — for chondrite and for spinifex-textured komatiites from Ghatti Hosahalli (India), Barberton (South Africa), Munro (Canada), and Yilgarn (Australia) reveal that, except for the Ti/Zr ratio for the Ghatti Hosahalli komatiite, the other ratios from the four terrains define a unique trend that is almost superimposed on the trend defined by these ratios for chondrite. This suggests that the processes of formation of komatiitic lavas from the four far-separated terrains were similar, and that, the source regions from which these lavas formed had a chondritic composition.