The rocks are exposed along two spillway walls that are approximately 300' apart. Major cycles of sandstone deposition are separated by 10' - 30' thick shales of hemipelagic or debris flow origin. Turbidites are the result of a type of gravity sedimentation. One or more of the intervals may be missing. Click on section for larger view.
Chaotic deposit separates two major cycles of sandstone deposition.
Each bed represents a separate depositional episode. Brian gives us an idea of the thickness of this chaotic deposit. Thin beds of sandstone and shale. Typically, the uppermost beds in a package are thinner and show flat bases and tops. Sam and Ron inspect massive sandstone and conglomerate beds near the top of the section.