| OCR Text |
Show 60 warming can take place if the groundwater circulates along fracture zones to depths of several thousand feet. Groundwater may also be warmed in convection cells surrounding hot spots in the earth's crust, such as shallow magma chambers. Warm water is yielded by some shallow wells in each of the areas around Great Salt Lake. These warm- well waters range in temperature from 70 to 80 degrees, but are not warm enough to provide direct evidence of geothermal reservoirs in the areas surrounding the Lake. However, the warm temperatures should be noted and the reservoir temperature calculations should be made in the course of any regional exploration for geothermal resources. Precipitation on the Lake Precipitation directly over the Lake surface provides about a fourth of the total yearly inflow. The amount of this precipitation depends not only on the average precipitation but on the surface area of the Lake. Because the surface area varies with changes in Lake level, the direct contribution from precipitation also varies. During June, 1925, when the Lake was at a relatively high level ( 4202 feet above sea level), the monthly contribution from precipitation was 300,000 acre- feet of water from an average of 2.79 inches of precipitation over the Lake surface. Since 1925, the maximum contribution during any one water year from precipitation has been estimated to be 1,500,000 acre- feet of water, which occurred during 1925 when the Lake area was high. GREAT SALT LAKE LEVELS The elevation of the Great Salt Lake, since 1850 when records were |
