Description:
The San Carlos-Safford-Duncan Nonpoint-Source Management Zone (Figure 1) is known to
contain significant quantities of geothermal energy resources. Following the energy crisis in the
1970s, these resources were studied in detail. This report includes references pertaining to
geothermal energy resources, hot springs and wells, heat flow measurements, and geothermal
gradients.
Two geothermal reservoirs are located in Greenlee County. One ofArizona's most
important Known Geothermal Resource Areas (KGRA) is at Clifton. References pertaining to
geothermal resource evaluations for Greenlee County and the Clifton KGRA include Witcher
(1979a), Arizona Geothermal Commercialization Team( 1979), Witcher and Stone (1980),
Witcher (1981), and Hahman (1979a, b).
The Safford basin, in Graham County, contains at least four proven and potential
geothermal reservoirs of less than 1.2 km depth and three inferred moderate to high-temperature
reservoirs less than 2.5 kIn depth (Arizona Geothermal Commercialization Team, 1979). Studies
by Witcher, 1979b, 1981, 1982) Rahman, (1979a) and Halnnan and others (1979) focused on
characterizing the nature and extent ofgeothermal anomalies in the Safford area.
(7 pages)