Advances in the Geothermal Exploration of the East Africa Rift System (original) (raw)

We review results of geological, geochemical and geophysical investigations carried out within the frame of recent geothermal surveys in the East African Rift System (EARS). In particular, we focus on three of the most important geothermal fields namely Alalobeda (Ethiopia), Menengai (Kenya) and Ilwalilo-Kilambo (Tanzania). These fields well represent the different structural, volcanological and hydrogeological realms that may be encountered in EARS. Alalobeda and Menengai are examples of two possible geothermal play types of the Eastern Branch of EARS. The former is a fault-leakage-controlled geothermal system, located in a half-graben structure, where the heat source is likely diffuse, deep-seated magmatism, associated to the lithosphere thinning that regionally affects this area. The reservoir temperature of this water-dominated system ranges from 185 to 225 °C. The Menengai geothermal field can be classified as a convection-dominated magmatic play-type, where the heat source cou...