A partially defined and largely unexplored confined aquifer in Colorado, Nebraska, and Wyoming is identified regionally through interpretation of geophysical logs, well drilling, coring, petrographic analysis, and GIS interpretation. The aquifer is a fine-grained arkosic sandstone, with thickness ranging up to 1000 ft in some areas. The aquifer represents a significant water resource for ranching and other development in northeastern Colorado and may be a resource for Wyoming, and Nebraska. Nomenclature for this aquifer is suggested. Water wells penetrating the entire aquifer have produced up to 200 gpm. Water quality data is presented including total dissolved solids, boron, and microbial methane.
