COMPARATIVE STUDIES OF SOLAR, Q-GASES AND TERRESTRIAL NOBLE GASES, AND IMPLICATIONS ON THE EVOLUTION OF THE SOLAR NEBULA

Abstract

We selectively review noble gas data for the Earth and meteorites (the Q component) and for the sun (solar wind) and seek to understand possible genetic relationships among these components. The widespread distribution of Q gases suggests that it was established as a distinct component prior to incorporation in planetary solids, e.g., in the gas phase of the solar nebula. We suggest that mass might be the major factor involved in generating both elemental and isotopic fractionations which characterize Q, e.g., by some form of Rayleigh distillation. The empirical relationship between Q and its presumed antecendant solar-composition source reservoir further suggests that He in Q is post-deuterium-burning He, implying active exchange of materials between the early sun and the solar nebula. A comparison of terrestrial noble gases with Q and solar wind suggests that primordial terrestrial gases are unlikely to have been derived from either component alone, even with some superposed fractionation; a mixture of the two components is a more plausible source.