The distribution of Cr, Ni, and chromite in komatiites, and application toexploration for komatiite-hosted nickel sulfide deposits

A comprehensive review of literature on the data on Ni and Cr contents in k omatiites reveals that barren and mineralized komatiite sequences show cont rasting trends on plots of Cr versus Ni. Barren komatiite sequences, on the average, have substantially higher Cr contents and Cr/Ni ratios than miner alized sequences. This contrast is due to the strong association of mineral ization with volcanic facies involving channelized flow, and there is no su ch contrast between barren and mineralized flows within samples from channe lized flow environments. Ponded sheet flow and lava lake sequences, with lo w potential for hosting economic nickel sulfides mineralization, can be dis criminated on the basis of their statistically higher Cr contents and Cr/Ni ratios than more prospective sequences.