Structure contours of base of upper Arapahoe aquifer in "Structure, outcrop, and subcrop of the bedrock aquifers along the western margin of the Denver Basin, Colorado." Hydrologic Atlas 742

These data were released prior to the October 1, 2016 effective date for the USGS’s policy dictating the review, approval, and release of scientific data as referenced in USGS Survey Manual Chapter 502.8 Fundamental Science Practices: Review and Approval of Scientific Data for Release. This digital geospatial data set consists of structure contours on the base of the upper member of the Arapahoe aquifer. The U.S. Geological Survey developed this data set as part of a project described in the report, "Structure, Outcrop, and Subcrop of the Bedrock Aquifers Along the Western Margin of the Denver Basin, Colorado" (Robson and others, 1998).