Zur Frage der Diffusionsverluste von radiogenen und spallogenen Edelgasen aus Steinmeteoriten

Abstract

Using a newly developed technique of specific solvents we succeeded in measuring the rare gas contents of the main mineral fractions of stone meteorites separately. In this way we studied the diffusion loss of the radiogenic and spallogenic rare gases in 5 chondrites which all had U-Th-He ages considerably below 4.5 billion years. The results showed that in 4 of these meteorites, which all belong to the UREY—CRAIG group L, no diffusion losses occurred during the time of cosmic ray exposure. Only in one of the meteorites, i. e. Breitscheid, (group H) large diffusion losses of the cosmic ray produced 3He were found. Considerable losses of radiogenic 4He could be proved for the meteorites Breitscheid and Bruderheim. For the meteorite Breitscheid the loss of 4He seems to be approximately a factor of 2 lower than that of 3He.