| A view generally southward to mostly the east side of the dirt path through the southern end of Lost Burro Gap. Exposed here is at the exact contact between two Paleozoic Era geological periods. The brownish outcrop at left lies at the very top of the Middle to Upper Devonian Lost Burro Formation; it is therefore very latest Devonian in geologic age. Behind that point, lies the bluish Lower Mississippian Tin Mountain Limestone. Geologic age of the precise point where the Lost Burro and Tin Mountain meet is 358.9 million years--transitional Devonian to Mississippian age. Photograph courtesy "Destination4x4". |