Strontium isotopes in carbonate deposits at Crater Flat, Nevada

Strontium isotope studies of carbonates from soils, veins, eolian dust and Paleozoic basement sampled near Crater Flat, southwest of Yucca Mountain, provide evidence for the origins of these materials. Vein and soil carbonates have nearly identical ranges of 87Sr/86Sr, and eolian material has 87Sr/86Sr ratios at the lower end of the pedogenic range. The average 87Sr/86Sr of Paleozoic basement from Black Marble Hill is similar to the 87Sr/86Sr in the eolian dust, perhaps indicating a local source for this material. Possible spring deposits have generally higher 87Sr/86Sr than the other carbonates. These data are compared with similar data from areas east of Yucca Mountain.