Potassium, rubidium, strontium, thorium, uranium, and the ratio of strontium-87 to strontium-86 in oceanic tholeiitic basalt

M. Tatsumoto; C. E. Hedge; A.E.J. Engel

doi:10.1126/science.150.3698.886

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Potassium, rubidium, strontium, thorium, uranium, and the ratio of strontium-87 to strontium-86 in oceanic tholeiitic basalt

M. Tatsumoto·C. E. Hedge·A.E.J. Engel

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Abstract

The average concentrations of potassium, rubidium, strontium, thorium, and uranium in oceanic tholeiitic basalt are (in parts per million) K, 1400; Rb, 1.2; Sr, 120; Th, 0.2; and U, 0.1. The ratio Sr 87 to Sr 86 is about 0.702, that of K to U is 1.4 x 10 4 , and of Th to U is 1.8. These amounts of K, Th, U, and radiogenic Sr 87 are less than in other common igneous rocks. The ratios of Th to U and Sr 87 to Sr 86 suggest that the source region of the oceanic tholeiites was differentiated from the original mantle material some time in the geologic past.

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M. Tatsumoto, C. E. Hedge, A.E.J. Engel. 1965. Potassium, rubidium, strontium, thorium, uranium, and the ratio of strontium-87 to strontium-86 in oceanic tholeiitic basalt. https://doi.org/10.1126/science.150.3698.886

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