Noble Gas Characteristics in Tektites
Physics and Astronomy
We have determined the elemental and isotopic composition of all the noble gases in five large samples of tektites from Bedias, Texas. The purpose of this study is to determine the abundance pattern of noble gases in these samples for comparison with those determined in tektites from other strewn fields throughout the world. One prominent feature that showed up in all of these tektites is the enormous enrichment of Ne, by up to a factor of few thousand, relative to the air. The isotopic composition of Ne in all these tektites is quite similar to that of air, suggesting that Ne in these tektites is of atmospheric origin. The light noble gas results alone do not seem to be sufficient to draw clear distinctions in tektites from the major strewn fields in Australia, Czechoslovakia, and North America. Our work suggests that the heavy noble gases Kr and Xe may provide a way of distinguishing bediasites from other tektite groups. The F(m) values for Xe fall between approximately 100 and 300 in bediasites, where as the F(m) values determined in tektites from the other strewn fields lie between 2 and 10. It appears that the heavy noble gas results in bediasites are clearly different than those values determined in tektites from other strewn fields. We will examine whether the heavy noble gas enrichments in bediasites can also be understood from the view-point of diffusion of atmospheric gases into these tektite glasses. In addition, the enrichment of heavy noble gases in bediasites seem to provide clues about the noble gas composition of source rocks or sediments from which these glassy objects are generated by impact.
Presented at the 57th Annual Meeting of the Meteoritical Society.
R.L. Palma and M.N. Rao, 1994. Noble Gas Characteristics in Tektites. Meteoritics 29, No. 4, 515.
Publisher's Copyright and Source
Copyright © 1994 The Meteoritical Society. Article published by John Wiley and Sons in Meteoritics, volume 29, issue number 4, July 1994, page 515.