The particle track record of Fra Mauro.Apollo 14 breccias show a mixture of high and low track densities at most interior positions, indicating that the majority of the tracks have been inherited from the parent ingredients of the breccias. Using the lowest of these track densities as indicative of maximum postbrecciation surface residence times, we find a median 1.35 m.y., much younger than the less friable Apollo 11 and 12 igneous rocks. The igneous rock 14310 is studied as a part of a consortium, the results indicating a complex irradiation history. Soils are extremely variable, median track densities ranging over at least a factor of 200. Individual high density soil grains yield track density gradients having variable slopes, most of which are lower than expected from the Surveyor III filter glass results.
Document ID
19730035069
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Hart, H. R., Jr.
Comstock, G. M.
Fleischer, R. L. (GE Research and Development Center Schenectady, N.Y., United States)