Numerous potassium-argon ages have been determined on a variety of rocks from the Altiplano of Bolivia with the intent of providing data on the three following problems: (a) ages of the batholiths that intrude early Paleozoic sedimentary rocks along the Cordillera Real and Quimza Cruz; (b) ages of ore mineralization from Sorata to Potosi; and (c) stratigraphic relations and ages within the thick, largely nonfossiliferous Tertiary deposits of the Altiplano Basin.It is shown that all batholithic masses north of Illimani are of Triassic-Jurassic age as is the tin mineralization found within the rocks. Illimani and all major intrusions to the south as far as the Kari Kari batholith have ages of 19 to 26 m.y. Ore mineralization as young as late Pliocene or early Pleistocene is shown to exist. Volcanic rocks within the Tertiary deposits, together with extensive field mapping by the Geologic Survey of Bolivia, are adequate to allow elucidation of the major features of, and stratigraphic correlations within, the Tertiary deposits.

First Page Preview

First page PDF preview
You do not currently have access to this article.