Rare gas diffusion studies in individual lunar soil particles and in artificially implanted glasses

The linear heating technique was applied to study the release of solar wind implanted He and Ne in single glass spherules and minerals of lunar soils. In addition, the diffusion of rare gases artificially implanted into simulated lunar glass was investigated. Activation energies derived for lunar glasses are much higher than for virginal glasses of similar chemical composition. Volume diffusion of the lunar surface cannot explain the high retentivity for the trapped gases. It is expermentally shown that various types of radiation damage are of paramount importance to the understanding of the secondary alterations of elemental abundances after solar wind implantation on the lunar surface.Paper dedicated to Prof. Harold C. Urey on the occasion of his 80th birthday on 29 April 1973.