The Prairie Canyon Project

Delta-Fed Turbidite Sands: Evaluating a New Depositional Model for Isolated, Thin-Bedded Marine Sandstone in the Cretaceous Western Interior Seaway

Project Summary

This project studied the Prairie Canyon Member (PCM) of the Mancos Shale as an outcrop and subsurface analog for delta-fed turbidite sand (DFTS) plays in the Rocky Mountain region. Of several potential DFTS intervals in the Rocky Mountains, the PCM is the only one that has sufficeint high-quality outcrop and nearby subsurface production to evaluate and discriminate between various geologic models advanced for DFTS. As an analog, the PCM model can be applied to other potential sand plays in the greater Rocky Mountain region, an under-explored area with significant gas potential.

This study quantified the predominant channel and sheet architecture of the PCM by making regional shelf-to-basin correlations, establishing a stratigraphic framework for the multiple, shingled sandstone lenses, documenting proximal-to-distal depositional patterns that link the outcrop to subsurface production, and relating outcrop architecture, facies, and lithology patterns to the most productive subsurface intervals. Research methods intergrated geologic mapping, section measuring, and subsurface analysis to develop play maps and evaulate a geologic model for this poorly understood deposit type.