Oxygen, Silicon, and Aluminum in Lunar Samples by 14 MeV Neutron Activation

Abundances of oxygen, silicon, and altiminutm in 27 lunar rocks and C aliquants of lunar soil have been determined by 14 MeV neutron activation. Mean abundances and standard deviations of individual abundances (in weight percent) within each type are: type A (2 rocks), 38.5 +/- 1.2 oxygen, 18.9 +/- 0.8 silicon, and 4.0 +/- 0.4 aluminum; type B (7 rocks), 39.4 +/- 1.0 oxygen, 18.7 +/- 0.8 silicon, and 5.0 +/- 0.6 aluminum; type C (18 rocks), 41.1 +/- 1.0 oxygen, 19.7 +/- 0.7 silicon, and 6.6 +/- 0.5 aluminum; soil (3 aliquants), 40.8 +/- 1.2 oxygen, 20.2 +/- 0.2 silicon, and 7.2 +/- 0.1 aluminum. Oxygen abundances are lower than those in most common terrestrial rocks and are comparable to those found in certain types of stony meteorites. From these results the lunar soil is most similar to the type C lunar rocks.