Bulk oxygen isotope compositions of equilibrated ordinary chondrite falls using CO2 laser-BrF5 fluorination technique

Abstract

Oxygen isotopic compositions of equilibrated ordinary chondrites were analyzed using CO2 laser fluorination system. (1) Data define a much sharper mixing line than those of Clayton et al.(1991).(2) There is neither overlap nor cap between our L and LL data. (3) There are good correlations between oxygen isotopes and some bulk siderophiles. (4) A positive correlation between Co in kamacite and fayalite contents of OCs has been known. The high-Co (>100 mg/g) and high-fa (>31 mol.%) LL members generally have higher Δ17O values.