| A Google Earth street car perspective that I edited and processed through photoshop. The view is slightly northwest of due south along a road in Ventura County--a county that is contiguous with Santa Barbara County. That roadcut at left exposes Oligocene (about 28 million years old) bone-bearing sediments of the middle Eocene to lower Miocene (roughly 42 million to 20 million years ago) Sespe Formation, one of the most famous Cenozoic Era vertebrate fossil-bearing geologic rock units in all of southern California. Even though the Sespe sedimentary accumulation indeed represents a considerable interval of depositional history, spanning some 22 million years, the stratigraphic reality is that in most exposures practically all of the late Eocene through Early Oligocene time is completely missing, a period of roughly 12 million years when erosion removed much Sespe material, creating a dramatic disconformity in the geologic record. |