LU-HF ISOTOPE SYSTEMATICS OF NWA4468 and NWA2990: IMPLICATIONS FOR THE SOURCES OF SHERGOTTITES
نویسندگان
چکیده
OF SHERGOTTITES T. J. Lapen, M. Righter, A. D. Brandon, B. L. Beard, J. Shafer, A. J. Irving, Department of Geosciences, University of Houston, Houston TX 77204-5007 ([email protected]), NASA-Johnson Space Center, Mail Code KR, Houston TX 77058, Department of Geology and Geophysics, University of Wisconsin-Madison, Madison WI 53706, NASA Astrobiology Institute. Dept of Earth & Space Sciences, University of Washington, Seattle WA.
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Combined chemical separation of Lu, Hf, Sm, Nd, and Rees from a single rock digest: precise and accurate isotope determinations of Lu-Hf and Sm-Nd using multicollector-ICPMS.
A combined procedure for separating Lu, Hf, Sm, Nd, and rare earth elements (REEs) from a single sample digest is presented. The procedure consists of the following five steps: (1) sample dissolution via sodium peroxide sintering; (2) separation of the high field strength elements from the REEs and other matrix elements by a HF-free anion-exchange column procedure; (3) purification of Hf on a c...
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