Cosmic-ray-produced stable isotopes in iron meteorites
Journal Article
·
· Journal of Geophysical Research
The isotopic composition of vanadium, calcium, and potassium extracted from several iron meteorites was measured. The isotopes V⁵⁰, Ca⁴⁶, Ca⁴³, and K⁴⁰ were found to be strongly enriched by cosmic-ray- induced spallation reactions. The concentrations of these isotopes were determined by isotopic dilution techniques. The results are compared with data on cosmogenic Sc/sup 45/ and rare gas isotopes in order to determine the distribution of stable spallation products. The concentration C(A,Z) of a stable spallation product can be given as a function of the total mass loss DELTA A = 56 -- A by the equation C(A,Z) = gamma (A,Z)k₁( DELTA A)-k₂ where gamma = 1 for cumulative and 0 < gamma < 1 for noncumulative isotopes. This equation is experimentally verified for a wide range of DELTA A. The constants k₁ and k₂ were calculated for each meteorite. Especially from the constants k₂ we obtain information concerning the location of the samples inside of the preatmospheric meteorite bodies. Exposure ages were estimated by comparing the concentrations of K⁴⁰ with those of stable isotopes. Comparison with Cl₃₆-Ar₃₆ exposure ages indicates an essentially constant cosmic-ray bombardment during the time of exposure. (auth)
- Research Organization:
- Univ. of California, San Diego
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-17-003177
- OSTI ID:
- 4761931
- Journal Information:
- Journal of Geophysical Research, Journal Name: Journal of Geophysical Research Journal Issue: 9 Vol. 67; ISSN 0148-0227
- Publisher:
- American Geophysical Union
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
COSMIC-RAY-INDUCED STABLE AND RADIOACTIVE NUCLIDES IN METEORITES
NUCLEAR REACTIONS IN IRON METEORITES
Cosmic-ray exposure records and origins of meteorites
Technical Report
·
Sat Jun 01 00:00:00 EDT 1963
·
OSTI ID:4693821
NUCLEAR REACTIONS IN IRON METEORITES
Journal Article
·
Sat Dec 31 23:00:00 EST 1960
· Geokhimiya (U.S.S.R.) For English translation 1956-63 see Geochemistry (USSR)
·
OSTI ID:4819914
Cosmic-ray exposure records and origins of meteorites
Conference
·
Mon Dec 31 23:00:00 EST 1984
·
OSTI ID:5516997
Related Subjects
AGE ESTIMATION
CALCIUM
CALCIUM 40
CALCIUM 46
COSMIC RADIATION
DISTRIBUTION
ENRICHMENT
GEOLOGY, MINERALOGY, AND METEOROLOGY
ISOTOPE DILUTION
ISOTOPES
MEASURED VALUES
METEORITES
NUCLEAR REACTIONS
POTASSIUM
QUANTITATIVE ANALYSIS
QUANTITY RATIO
RADIATION EFFECTS
RARE GASES
SCANDIUM 45
SOLUTIONS
SPALLATION
VANADIUM
VANADIUM 50
CALCIUM
CALCIUM 40
CALCIUM 46
COSMIC RADIATION
DISTRIBUTION
ENRICHMENT
GEOLOGY, MINERALOGY, AND METEOROLOGY
ISOTOPE DILUTION
ISOTOPES
MEASURED VALUES
METEORITES
NUCLEAR REACTIONS
POTASSIUM
QUANTITATIVE ANALYSIS
QUANTITY RATIO
RADIATION EFFECTS
RARE GASES
SCANDIUM 45
SOLUTIONS
SPALLATION
VANADIUM
VANADIUM 50