Geothermal resource potential of Willcox Area, Arizona

Willcox, Arizona, established in 1880 when the Southern Pacific Railroad was built, lies on the east edge of the Willcox Playa at the northwest base of the Dos Cabezas Mountains in the Sulphur Springs Valley of southeastern Arizona (Fig. 1). The Sulphur Springs Valley, named for the no longer flowing springs at the base of low hills south of the playa, is underlain by the sediment filled Willcox basin. While sulphurous springs are frequently thermal and may indicate significant geothermal energy potential, the namesake springs in the valley are not believed to have been thermal. However, several wells drilled for irrigation and domestic water supplies have encountered thermal water (>30 degrees C). This report summarizes and discusses these occurrences in context to their geologic and geohydrologic settings. An additional goal of this study is to identify areas in the Willcox basin, which have geothermal resource potential. Because the Willcox area has a large agricultural economic base and has relatively cool nights in the winter, significant opportunities exist for direct use of geothermal heat. Agricultural and space heating applications best utilize lower temperature resources. Possible development of geothermal resources in the Willcox area may be advantageous in saving energy and conserving ground water. Many forms of geothermal agriculture such as greenhouses use far less ground water per acre for irrigation than conventional crops such as cotton. (39 pages)Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact azgs-info@email.arizona.edu