Figure F46. Mg# vs. TiO2 for Leg 192 basalt and volcaniclastic rocks. The basalt group from Hole 1185A and Units 1-9 of Hole 1185B (upper group) has a rather similar range of Mg# to that of Units 10-12 in Hole 1185B (lower group). However, the lower Mg# of some of the lavas in the lower part of Hole 1185B could be a result of alteration. Mg# is calculated assuming that 12% of the iron is Fe3+, which is equivalent to Fe2O3/(Fe2O3) + FeO) = 0.13, or Fe2O3/FeO = 0.15.

Figure F46. Mg# vs. TiO₂ for Leg 192 basalt and volcaniclastic rocks. The basalt group from Hole 1185A and Units 1-9 of Hole 1185B (upper group) has a rather similar range of Mg# to that of Units 10-12 in Hole 1185B (lower group). However, the lower Mg# of some of the lavas in the lower part of Hole 1185B could be a result of alteration. Mg# is calculated assuming that 12% of the iron is Fe³⁺, which is equivalent to Fe₂O₃/(Fe₂O₃) + FeO) = 0.13, or Fe₂O₃/FeO = 0.15.