EVIDENCE FOR A NON-COSMOGENIC IMPLANTED C-14 COMPONENT IN LUNAR-SAMPLES

Experiments to determine if the presence could be confirmed of excess C-14 implantation in lunar soils and a rock surface sample were undert aken. Stepwise HF etchings of near-surface lunar soil 73221, collected from 0 to 0.5 cm depth and surface soil 10084, and a sample of surfac e scrapings from rock 68815 released appreciable amounts of C-14. Cons idering the amount of material dissolved, we find that the amounts of C-14 released are significantly in excess of the amounts that would be necessary for both galactic and solar cosmic-ray-produced C-14, even for the very surface. Further, there is an excess of C-14 released com pared to deeper samples of rock and soil, based on our analyses of sub surface soils (73241 and 73261) from the same trench location of 73221 , and earlier studies of C-14 in rock 68815 [1]. Based on the observed release pattern of C-14, we estimate that the excess C-14 in the luna r surficial samples may be released from depths of up to several micro ns. We conclude that this is an implanted solar component.