Precision measurement of lead isotopes ratios: preliminary analyses from the U.S. mine, Bingham Canyon, Utah

J. S. Stacey; W. J. Moore; R.D. Rubright

doi:10.1016/0012-821x(67)90195-1

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Precision measurement of lead isotopes ratios: preliminary analyses from the U.S. mine, Bingham Canyon, Utah

J. S. Stacey·W. J. Moore·R.D. Rubright

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Abstract

A gas-source mass spectrometer has been constructed for the precise measurement of lead isotope ratios. Sixteen analyses on 4 different preparations of the same galena made over a period of 2 months gave 95% confidence limits (per analysis) of 206 Pb/ 204 Pb= 0.080%, 207 Pb/ 206 Pb= 0.042%and 208 Pb/ 206 Pb= 0.046% . Eight samples from the U.S. mine in the Bingham district have a linear relationship over the 1% range of their 206 Pb/ 204 Pb ratios. The simplest model fitting these data suggests that the lead was separated from a primary system (μ=8.98) 1630±150m.y. ago and subsequently mixed with a radiogenic lead of similar age; biotite K-Ar dates for altered intrusive rocks associated with the ores provide an apparent age of mineralization and suggest that isotopic evolution of the lead was terminated about 36 m.y. ago.

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Earth and Planetary Science Letters Article

Source-reported bounding extent: 40.21250278039901° to 40.61550688525992° latitude; -112.3599157983052° to -111.85271775878975° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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J. S. Stacey, W. J. Moore, R.D. Rubright. 1967. Precision measurement of lead isotopes ratios: preliminary analyses from the U.S. mine, Bingham Canyon, Utah. https://doi.org/10.1016/0012-821x(67)90195-1

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