DEUTERIUM CONCENTRATION IN THE EARLY SOLAR-SYSTEM - HYDROGEN AND OXYGEN ISOTOPE STUDY

D/H ratios in the unequilibrated chondrite Chainpur range up to 9 x 10 -4. Corresponding 17O contents are 1‰ higher than in other LL chondrites, with varying 18O contents. These results are discussed in terms of low temperature condensation of water and early irradiation by intermediate energy protons. The latter explanation is favoured. © 1979 Nature Publishing Group.