wikipedia has some useful overview info on kambalda type...

wikipedia has some useful overview info on kambalda type komatiitic nickel ore deposits.

http://en.wikipedia.org/wiki/Kambalda_type_komatiitic_nickel_ore_deposits

Some extracts:

The genetic model of Kambalda-type NiS ore deposits is similar to the broader category of magmatic Ni-Cu-PGE ore deposits:

-Source: Highly magnesian ultramafic melts which become sulfur saturated during ascent, or upon contact with the surface
-Transport: Typically, the transport of the komatiitic melts in the Kambalda type NiS ore deposits is considered to represent a mantle plume tail impinging on a continental rift or margin. The nickel is transported within the highly ultramafic high-temperature melt.

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The lava channel is typically recognised within a komatiite sequence by;

-Thickening of the basal flow of the komatiite sequence
-Increased MgO, Ni, Cu, and concomitant decrease in Zn, Cr, Fe, Ti as compared to 'flanking flows'


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