Application of the sphalerite cosmobarometer to group IAB iron meteorites

Sphalerite compositions from ten members of iron meteorite group IA and one member of group IB were determined and pressures (P350) calculated, assuming a blocking temperature for Fe diffusion of 350°C. Although three meteorites, Ogallala and Copiapo (IA) and Woodbine (IB), yielded clearly outlying values, the remaining eight members of group IA yielded pressures that were linearly correlated with 1(wt.% Ni) of the meteorite. The equation of …