26Al (dpm/kg) and or He, Ne, and Ar have been measured in samples of the Norton County meteorite from three different depths. The gas contents yield a shielding-corrected age of 75.8¿5.7 m.y. The ratio fo atomic production rates P(26Al)/P(21Ne) is 0.22¿0.02. 3He, 21Ne, and 26Al increase with decreasing 22Ne/21Ne at nearly the same rates as they do in the smaller Keyes chondrite. 26Al contents were measured in Bustee (75.9¿3.3), Khor Temiki (89.9¿3.5), Pesyanoe (98.4¿3.4), and Shallowater (62.8¿2.0) meteorites. 26Al/26Al0 correlates with 22Ne/21Ne, and comparison with the corresponding chondrite correlation indicates that the aubrites, like Malakal, may have experienced an unusually high flux of cosmic rays. |