blackfoot-valley

granite before being later exposed by erosion of the material above it). These are far older than the water-and ice-deposited material just described. Interspersed with these in the same western hills of the Ranch are sedi- mentary rocks of various ages, but mostly preceding the ice ages. (For those of geologic bent, rocks from the Tertiary age in the Ranch’s northern, that is, Wales section can be found as well as those from the Paleozoic period found in parts of Murray Creek and the southern section.) Finally, there are major occurrences of crystalline metamorphic rocks such as argillite, as well as one of the very hardest and most resistant rocks on earth, Quartzite, in the hills behind Wales Creek Reservoir in the north section of the Ranch. 30