Abstract
We have applied a new geochronometer, based on the decay of 138La to 138Ba, to a sample of Amîtsoq gneiss from West Greenland. Using a value for the electron-capture decay constant, λEC, of 4.44 × 10−12 yr−1, the resulting age (2,408 ± 24 Myr) is in good agreement with that from Sm–Nd systematics (2,410 ± 54 Myr). Application of this geological clock is limited to REE (rare earth element)-rich minerals, but its merit is that, for Archaean rocks, the age can be evaluated from one specimen on the assumption that the initial Ba isotope ratios are effectively constant.
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References
Tanaka, T. & Masuda, A. Nature 300, 515–518 (1982).
Masuda, A. & Nakai, S. Geochem. J. 17, 313–314 (1983).
Eugster, O., Tera, F. & Wasserburg, G. J. J. geophys. Res. 74, 3897–3908 (1969).
Lewis, R. S., Anders, E., Shimamura, T. & Lugmair, G. W. Science 222, 1013–1015 (1983).
York, D.,Can. J. Phys. 44, 1079–1086 (1966).
Sato, J. & Hirose, T. Radiochem. radioanalyt. Lett. 46, 145–152 (1981).
Baadsgaard, H., Lambert, R. St J. & Krupicka, J. Geochim. cosmochim. Acta. 40, 513–527 (1976).
Galliker, D., Hugentobler, E. & Hahn, B. Helv. phys. Acta. 43, 593–606 (1970).
Ishimori, T. Nippon Genshiryoku Kenkyusho Kenkyu Hokoku 1102, 95–97 (1966).
Reizler, W. & Kauw, G. Z. Naturf. 12 A, 665–666 (1957).
Senftle, F. E., Stern, T. W. & Alekna, V. P. Nature 184, 630 (1959).
MacFarlane, R. D. & Kohman, T. P. Phys. Rev. 121, 1758–1769 (1961).
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Nakai, S., Shimizu, H. & Masuda, A. A new geochronometer using lanthanum-138. Nature 320, 433–435 (1986). https://doi.org/10.1038/320433a0
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DOI: https://doi.org/10.1038/320433a0
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