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Fine resolution chronology based on initial Sr-87/Sr-86It has been recognized that small variations in initial Sr-87/Sr-86 (Sr(sub I)), can provide a fine scale relative chronology for the chemical fractionation of materials with low Rb/Sr from parent reservoirs with high Rb/Sr. Similarly, Sr(sub I), as determined for low Rb/Sr phases in meteorites, may permit a fine resolution chronology of the recrystallization or metamorphism of planetary materials. For the establishment of a primitive Sr-87/Sr-86 chronology, it is important to search for samples with extremely low Rb/Sr for which the measured Sr-87/Sr-86 is below BABI, in which case the primitive nature of the Sr can be directly established. Using the measured Rb/Sr to calculate an initial Sr-87/Sr-86 can introduce substantial uncertainty if the Rb-Sr are disturbed. We report Sr-87/Sr-86 in plagioclase from silicate pebbles from the Vaca Muerta mesosiderite on which we have reported Sm-147-Nd-143 and Ne-142 correlations. For the purpose of cross-calibration with our previous work we have performed extensive new measurements on Angra dos Reis and on anorthite from Moore County, which have very low Rb/Sr and primitive Sr-87/Sr-86.
Document ID
19940016321
Document Type
Conference Paper
Authors
Stewart, B. W. (California Inst. of Tech. Pasadena, CA, United States)
Papanastassiou, D. A. (California Inst. of Tech. Pasadena, CA, United States)
Capo, R. C. (California Inst. of Tech. Pasadena, CA, United States)
Wasserburg, G. J. (California Inst. of Tech. Pasadena, CA, United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1993
Publication Information
Publication: Lunar and Planetary Inst., Twenty-Fourth Lunar and Planetary Science Conference. Part 3: N-Z
Subject Category
INORGANIC AND PHYSICAL CHEMISTRY
Report/Patent Number
CONTRIB-5230(794)
Funding Number(s)
CONTRACT_GRANT: NAG9-43
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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