RARE GASES AND POTASSIUM DETERMINATION IN A LARGE SAMPLE OF STONY METEORITES

Journal Article · Tue Jan 01 04:00:00 EST 1963 · Geochimica et Cosmochimica Acta (England)

DOI:https://doi.org/10.1016/0016-7037(63)90070-X· OSTI ID:4683856

Kirsten, T; Krankowsky, D; Zaehringer, J

The Re, Ne, and Ar isotopes of 59 and the total K content of 48 stony meteorites were determined. The isotopic composition of the spallation-produced rare gases is in agreement with production rates, calculated from the cosmic ray spectrum including secondaries and from crosssection measurements of high-energy protons. Different chemical composition of the various types of stony meteorites can account for the large variations of the measured isotopic ratios. In some cases a different effective bombarding energy due to the amount of shielding is indicated. The distribution of the amount of spallation products points to a continuous breaking of the meteorites rather than to a single event. The Re and K-Ar ages range from 0.2 to 5.1 x 10/sup 9/ yr and have a maximum in their distribution around 4,5 x 10/sup 9/ yr. A considerable number of meteorites have ages below 2 x 10/sup 9/ yr and some have large differences between the Re and K-- Ar ages. This can only be explained by an additional heating source after their formation. Heating by collisions seems to be more likely than by solar radiation. (auth)

• Research Organization: Max-Planck-Institut fur Kernphysik, Heidelberg
• NSA Number: NSA-17-030688
• OSTI ID: 4683856
• Journal Information: Geochimica et Cosmochimica Acta (England), Journal Name: Geochimica et Cosmochimica Acta (England) Vol. Vol: 27; ISSN GCACA
• Country of Publication: Country unknown/Code not available
• Language: German

Related Subjects

AGE ESTIMATION
ARGON
ARGON ISOTOPES
COLLISIONS
COSMIC RADIATION
CROSS SECTIONS
DISTRIBUTION
ENERGY
GEOLOGY, MINERALOGY, AND METEOROLOGY
HEATING
HELIUM ISOTOPES
METEORITES
NEON ISOTOPES
NUCLEAR REACTIONS
POTASSIUM
PROTON BEAMS
PROTONS
QUALITATIVE ANALYSIS
QUANTITY RATIO
SPALLATION
SUN
THERMAL RADIATION
VARIATIONS