| Abstract |
Thermal water samples were collected in North and South Kivu provinces of D.R. Congo, along the western branch of the East African Rift System (EARS). Surface temperatures range from 30ºC to 100ºC and the springs are neutral to alkaline. Chemical analysis of all samples show strikingly high bicarbonate content relative to the common major anions in hot springs, i.e., chloride and sulphate. Due the unusually high CO2 content in high temperature volcanic gases of the nearby Nyiragongo volcano, and due to the huge amount of dissolved magmatic CO2 in Lake Kivu, it is suggested that the high bicarbonate content in the springs stems from a constant supply of magmatic carbon dioxide to the geothermal system. Na-K geothermometers suggest underground temperature of 163 to 177 ºC for Mayi-ya-Moto site in North Kivu, which is promising for geothermal development. The entire eastern DRC along the western branch of EARS has geothermal potential and can therefore offer environmentally friendly alternative sources of electricity and heating. Detailed surface exploration is recommended. |