Galactic cosmic-ray-produced radionuclides in Antarctic meteorites and a lunar core

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:5967696

Fox, R L

Radionuclide depth effects in a meteorite, the history and pairing of Antarctic meteorites and processes on the lunar surface are discussed in six chapters. A depth profile of /sup 26/Al, /sup 10/Be and /sup 53/Mn activities have been measured in eleven metal phase samples of the Antarctic meteorite ALHA78084 to determine the importance of the secondary cascade in producing these nuclides in a 30 centimeter diameter meteorite. The results show a buildup of lower energy reaction products and a flat profile for high energy reaction products with depth. The activity of /sup 53/Mn has been measured as a function of depth in eleven soil samples from the lunar double drive tubes 15011/15010. The results agree within error with the previous results of Nishiizumi. These data are consistent with the previously published /sup 26/Al results of the Battelle Northwest group which indicated a disturbed profile down to 17 g/cm/sup 2/ and an accumulation rate of 2 cm/My. Comparison with the gardening models of Arnold and Langevin and the local topography suggests such a continuous accumulation is the result of steady downslope transport of surface soil for 7 to 10 My at this site. The /sup 53/Mn activity was determined in eleven samples in eight Allan Hills-80 Antarctic meteorites and one sample from an Elephant Moraine Antarctic meteorite. Mineralogic and field relation data suggest that Allan Hills meteorites to be two sets of paired falls. The /sup 53/Mn results are consistent with the grouping of these meteorites as paired falls excluding the meteorite ALHA80127. comparison with future nuclear particle track work and results from the measurement of other cosmogenic nuclides will provide more definitive results.

• Research Organization: California Univ., San Diego (USA)
• OSTI ID: 5967696
• Country of Publication: United States
• Language: English

Related Subjects

640101* -- Astrophysics & Cosmology-- Cosmic Radiation
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALKALINE EARTH ISOTOPES
ALUMINIUM 26
ALUMINIUM ISOTOPES
ANTARCTIC REGIONS
ANTARCTICA
BERYLLIUM 10
BERYLLIUM ISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
COMPARATIVE EVALUATIONS
CORRELATIONS
COSMIC RADIATION
COSMOLOGY
DEPTH
DIMENSIONS
ELECTRON CAPTURE RADIOISOTOPES
EVEN-EVEN NUCLEI
INTERMEDIATE MASS NUCLEI
IONIZING RADIATIONS
ISOTOPES
LIGHT NUCLEI
LUNAR MATERIALS
MANGANESE 53
MANGANESE ISOTOPES
MATERIALS
METEORITES
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
POLAR REGIONS
RADIATIONS
RADIOACTIVITY
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
YEARS LIVING RADIOISOTOPES