Geology and hydrology of the deep bedrock aquifers in eastern Colorado

Water-Resources Investigations Report 85-4240
By:  and 



Deep bedrock aquifers are present in rocks of Cretaceous through Pennsylvanian age in eastern Colorado. These aquifers are the Laramie-Fox Hills (the uppermost aquifer studied), Fort Hays-Codell, Dakota-Cheyenne, Entrada-Dockum, Lyons, and Fountain. Structural mapping indicates the aquifers are 2,000 to 9,000 ft below land surface in most of eastern Colorado but outcrop in local areas in a narrow band along the Front Range of the Rocky Mountains. Recharge primarily occurs in outcrops and produces a northerly or easterly groundwater flow to discharge areas along the South Platte or Arkansas Rivers. Deep aquifers also discharge by underflow to Kansas and Nebraska. Some water-yielding strata in the Dakota-Cheyenne aquifer are not in hydraulic connection with the aquifer, and abnormal fluid pressures, trapped hydrocarbons, and high dissolved-solids concentrations are found in these strata. Temperature and dissolved-solids mapping indicate water temperatures of 100 to 210 in northeastern Colorado and a zone of relatively fresh water extending through a 7,000 sq mi area of the Dakota-Cheyenne aquifer in southeastern Colorado. Water levels in the Laramie-Fox Hills aquifer continue to decline as much as 12 ft/yr in local areas near Denver. 

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Publication type Report
Publication Subtype USGS Numbered Series
Title Geology and hydrology of the deep bedrock aquifers in eastern Colorado
Series title Water-Resources Investigations Report
Series number 85-4240
DOI 10.3133/wri854240
Year Published 1987
Language English
Publisher U.S. Geological Survey
Description 6 Plates: 32.41 x 48.12 inches or smaller
Country United States
State Colorado
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