Fracture and Karst Features Affecting Reservoir Performance in a Mississippian Reservoir, Cheyenne County, Colorado

Kansas Geological Survey

KGS Open-file 2006-14

Cheyenne Wells & Smoky Creek Fields


Structure map on the base of the Morrow Shale/ top of Keyes Formation (BMS/KYS). Spergen producers (red), field outlines (green), 3-D seismic area (blue), high-angle basement fault (dashed black), and Precambrian shear zone (dashed blue) are shown. Wells with core are labeled.


Structure map on top of the St. Louis (color filled contours) corresponding to the Mississippian Unconformity surface, with isopach of the Keyes interval and the top of the St. Louis superimposed (black, 5 ft. contour interval). Numbers are isopach thickness. The Keyes is the basal Pennsylvanian accumulation in the area and thicks in this isopach may represent fill of local depressions on the unconformity surface.

Structure map on top of the Spergen. Legend as on BMS/KYS map above.

Isopach of Gross Spergen thickness. Legend as on BMS/KYS map above.


Structure and Isopach Maps

Last Modified May 2006