Strontium isotopic study of plutons and associated rocks of the southern Sierra Nevada and vicinity, California. Bulletin

Rubidium and strontium concentrations and (87)Sr/(86)Sr values are documented herein for samples of plutons and associated rocks from 238 locations in the southern Sierra Nevada and vicinity. The goals of the investigation were to determine ages of rock units, to aid in the separation of plutons in poorly exposed areas, to determine the pattern of variation of initial (87)Sr/(86)Sr (hereafter called Sr(i)) for plutons, and to constrain more rigorously the boundaries of the continental Sierran and Salinian-western Mojave terranes defined on the basis of the Sr(i) of their plutons by Kistler (1978) and by Kistler and Peterman (1978). These new data expand the boundaries of the Salinian-western Mojave terrane and make it part of the Panthalassan lithosphere that lies west of the tectonic boundary, whereas the Sierran terrane is made part of the North American lithosphere that lies east of the tectonic boundary.