C, O and Sr isotopic halos related to the giant McArthur River stratiform Zn-Pb-Ag deposit, northern Australia

An extensive C, O and Sr isotopic halo occurs within the dolomite component of dolomitic silt-stones that extend to the west and above the McArthur River Zn-Pb-Ag deposit. Dolomite within the halo is enriched in ¹⁸O and radiogenic Sr, and depleted in ¹³C compared with the regional dolomite outside the halo. The halo is interpreted to mark the extent of the brine pool in which the stratiform Zn-Pb deposit formed.