| Title | Characterization of the Natron Geothermal System: Rift Basin Dynamics and Volcanic Influence |
|---|---|
| Authors | Adonias Mkangala |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | geothermal exploration, hot springs, rift basin, volcanic influence |
| Abstract | The Natron geothermal prospect, located in the Arusha Region of northern Tanzania, represents a significant target for geothermal exploration due to its complex tectonic setting and active volcanism. This prospect is being developed and funded by the Tanzania Geothermal Development Company (TGDC), with initial surface studies conducted to create a geological conceptual model that will guide future detailed exploration projects. The study adopted an integrated approach, combining remote sensing data analysis, field validation of geothermal manifestations, and an extensive literature review to develop a comprehensive geological framework. Geological mapping revealed that the Natron Basin is characterized by recent volcanic and fluvial deposits, underlain by pyroclastics, trachyte, nepheline-carbonatite, and basaltic lava flows. Rift faults and volcanic features structurally define the area, particularly the Oldoinyo Lengai and Gelai volcanoes, which serve as the main heat sources for the geothermal system. The geothermal manifestations include hot springs with temperatures ranging from 45 to 55°C, and pH levels above 10. Preliminary findings indicate that the reservoir is hosted within fractured basaltic units and volcanic sediments. The Gelai dyke, which is over 10 km long and associated with the 2007 Oldoinyo Lengai eruption, is considered a significant heat source. The Natron geothermal system is a magmatic, medium- to high-temperature reservoir associated with deep crustal heat sources and fault-controlled permeability. The lacustrine sediments and altered volcanic lavas form a sealing layer that retains geothermal fluids. This geological framework underscores Natron’s potential for geothermal energy development and supports the need for further geophysical, geochemical, and drilling programs. |