Distribution of rare gases in the pyroxene and feldspar of the Khor Temiki meteorite - Eberhardt, P.; Geiss, J.; Grogler, N. (Elsevier)
From the matrix of the Khor Temiki aubrite three grain size fractions (2.9 μ, 6.2 μ, 11.1 μ) highly enriched in feldspar and three corresponding pyroxene grain size fractions were prepared. The concentrations and isotopic compositions of He, Ne and Ar were measured in these six fractions. Diffusion loss of radiogenic, spallation and trapped rare gases in the feldspar is evident. The pyroxene shows no diffusion loss of spallation produced isotopes, even in micron sized grains. In feldspar ^3^8Ar"s"p"a"l"l is not lost; up to 50% of the ^2^1Ne"s"p"a"l"l may have been lost; and virtually no ^3He"s"p"a"l"l is retained. ^4^0Ar is partially lost in the finest (2.9 μ) feldspar fraction. The trapped gases in the pyroxene show again a strong anti-correlation with the grain size. The feldspar contains less than 10% as much trapped ^4He as the corresponding pyroxene, approximately 30% trapped ^2^0Ne and between 60 to 80% trapped ^3^6Ar.
http://linkinghub.elsevier.com/retrieve/pii/0012-821X(66)90096-3
Keywords: TE-TZ; U