Within
the CDZ, MgO concentrations are once again elevated with SiO2
decreasing (Fig. S5e). In both the SDZ and CDZ, elemental Ni and Cr
concentrations are elevated (Appendix A3 Table A3), approaching
ore-grade values (Candela and Piccoli, 2005), and may suggest either
significant fluid-assisted alteration of serpentinite to clay (O'Hanley,
1996) or represent mineralogical signatures potentially inherited
from the protolith material. East of the CDZ to ~3313 m MD, SiO2