Cretaceous Blackhawk Formation Measured Section

Photographs of bedding and structures are linked to the black arrows - click to look, then back-button click to return to measured section.

Assignment:

Determine the depositional environment of each of the numbered units, 1-23.

Use the grain-size changes, sedimentary structures, and stacking patterns to make your decisions. Abrupt shifts record sudden deepening or shallowing events; these surfaces should be noted as flooding surfaces or unconformities.