Noble Gas Anomalies and Synthesis

There are two types of planetary noble gases. One containing isotopically " anomalous: argon ,krypton and xenon but isotopically " normal " helium and neon, was derived from outer stellar regions. The other, consisting almost entirely of isotopically " normal " argon, krypton and xenon with little or no helium or neon, was derived from inner stellar regions. Mixing of nucleosynthesis products from different regions of a supernova is responsible for the observed correlations between elemental and isotopic rations of planetary noble gases in different classes of meteorites. The solar system condensed directly frm the chemically and isotopically heterogeneous debris of a single supernova. There is no convincing evidence, however of separate nucleogenetic components in neon. Variations in the abundance pattern of planetary noble gases are primarily the result of stellar fusion reactions and physical adsorption, rather than gas solubility.