URANIUM AND THORIUM IN TEKTITES

Neutron activation analysis for uranium and thorium are reported for two australites, a javaite, a bediasite and a moldavite. A critical survey is made of published uranium and thorium abundances in tektites, and superior analyses selected. Uranium and thorium abundances in the tektite groups are compared with terrestrial sedimentary and acid igneous rocks. Granophyres match tektites most closely in the abundance of these two elements, but cannot be considered probable parent material for a terrestrial tektite origin because of their limited distribution. An extraterrestrial origin is also considered and a relationship in uranium and thorium abundance is observed between some achondrites and the tektites. © 1969.