Idealized Stratigraphic Cross Section of the Southern Denver Basin modified from Raynolds (1987)
This diagram (not to scale) shows an idealized cross section (modified from Raynolds (1987)) of the stratigraphy of the Denver – Julesburg Basin. The diagram highlights water aquifers and oil and gas reservoirs as far down as the Cretaceous Age Dakota Group and how basement rock movements can potentially provide for a favorable vertical localized fracturing that can compliment widespread small scale fracturing caused by a regional stress field applied during mountain building periods to the Niobrara Shale (deposited in an Cretaceous Age interior seaway) allowing for enhanced oil recovery via horizontal drilling methods and hydraulic fracturing technologies.
See the Colorado Geological Survey’s Rocktalk Newsletter from 2011 for a more in depth discussion of general Niobrara Geology. The newsletter contains many maps and diagrams that will be of interest to all who are interested in a broad overview of Colorado’s portion of the Niobrara Play.