Geothermal Resource Investigations: Imperial Valley, California. Site location report, deep geothermal test well

Data for use in siting a deep geothermal test well in the East Mesa area of Imperial County, California are summarized. The data relate to a geothermal anomaly known as the Mesa anomaly. It is concluded that the thermal feature forming the Mesa anomaly is a manifestation of a sizable convective hydrothermal system embracing an area of about 19 square miles and a considerable volume of saturated sediment in the Salton trough. The upper surface of the thermal feature between depths of 200 and 1,000 feet is irregular being shaped somewhat by ground-water movement. The area of greatest apparent heat flow is in SE/sup 1///sub 4/ of Sec. 6, T. 16 S., R. 17 E., and has a diameter of about /sup 1///sub 2/ mile. This area is an attractive drill site. The convective hydrothermal system regulating heat flow to the shallow subsurface is not known in detail but iso-resistivity maps suggest it exerts direct influence on near surface water temperature and salinity over an area of some 19 square miles. The mineral concentration of the ground water in this system will range from a minimum of about 3000 ppM to a probable maximum of about 30,000 ppM