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USGS · 70009945

Strontium isotopes in Quaternary basalts of southeastern California

Z. E. Peterman·I. S. E. Carmichael·A. L. Smith
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Abstract

Strontium isotopic variations ( 87 Sr/ 86 Sr of 0.7029 to 0.7052) in Quaternary basalts of southeastern California, USA, are not readily explained by assimilation of crustal material similar to that contained as xenoliths in the basalt. Isotopic differences between chrome diopside (0.7016) and olivine (0.7087) from a lherzolite xenolith suggest that the isotopic variations in the basalts may be inherited from the source regions or modified by the upper parts of the mantle that were traversed by the lavas.

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Z. E. Peterman, I. S. E. Carmichael, A. L. Smith. 1970. Strontium isotopes in Quaternary basalts of southeastern California. https://doi.org/10.1016/0012-821x(70)90078-6

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