Preliminary Investigations of Geothermal Areas in Uganda, Other Than Katwe-Kikorongo, Buranga and Kibiro

Abstract

Preliminary geothermal investigations have been carried out on the other geothermal areas out side the active volcanic belt in Southwest, West, North and North-east Uganda. Previuos studies had focused on three areas Katwe, Buranga and Kibiro which were considered as most promising because of their volcanic and tectonic features. The aim of the the study was to select other areas for cascadede geothermal exploration and development.

The geochemical results indicate a good agreement between the Na/K and the silica geothermometer temperatures in some areas. The magnesium concetration is high in most of the samples suggesting a substancial influence of cold groundwater. Subsurface temperatures have been predicted with reasonable certainity for 8 of the 23 areas. The most promising areas based on permeability and their subsurface temperatures are Rubaare (134 - 140¢ªC), Kitagata (120 - 140¢ªC) and Kanangorok (140 - 160¢ªC) with reliable Na/K and silica geothermometers. The presence of hydrogen sulphide in Ihimbo (80. 100¢ªC) and Panyimur (80 - 120¢ªC) waters suggest that these sources might be hotter than predicted by geothermometry. Another group worth investigating includes Birara (140 - 160¢ªC), Minera (120. 130¢ªC) and Rubabo (120. 140¢ªC) whose subsurfaces temperature predictions using the silica and Na/K geothermometers are in agreement. The rest of the areas are good for direct uses in Industry and agriculture.