Survey for critical raw materials in Rwanda East African Rift geothermal areas
Cite as:
Wilke, Franziska D. H.; Ntihabose, Leon; Karangwa, Eugene; Stammeier, Jessica; Zimmer, Martin; Strauch, Bettina; Niedermann, Samuel; Regenspurg, Simona (2026): Survey for critical raw materials in Rwanda East African Rift geothermal areas. GFZ Data Services. https://doi.org/10.5880/GFZ.DMJQ.2026.002
Status
I N R E V I E W : Wilke, Franziska D. H.; Ntihabose, Leon; Karangwa, Eugene; Stammeier, Jessica; Zimmer, Martin; Strauch, Bettina; Niedermann, Samuel; Regenspurg, Simona (2026): Survey for critical raw materials in Rwanda East African Rift geothermal areas. GFZ Data Services. https://doi.org/10.5880/GFZ.DMJQ.2026.002
Abstract
The East African Rift System (EARS) continues south of the Afar Crossing in Ethiopia through Kenya and then splits into two branches: the western branch, which runs through Uganda and Rwanda, and the eastern branch, which runs through Tanzania. Both unite in Malawi. Magmatic activity began 20 million years ago south of Lake Turkana (Kenya). Here, destabilisation of the continental lithosphere and extrusion of phonolitic floods occurred, and after a phase of resurgence, small-scale ultra-alkaline, Si-saturated activity took place between ca. 5.9 and 2.9 Ma, defining the early rift development and volcanic initiation phase. Volcanism in the western branch of the EARS is confined to four spatially restricted provinces, all of which are found at the tips of long boundary faults or in accommodation zones between rift segments (Ebinger et al., 1989).
In autumn 2024, an expedition to Rwanda was undertaken within the framework of the research project “CRM-geothermal”. Within „CRM-geothermal“, we are looking for an environmentally friendly co-production of critical raw materials together with the provision of geothermal energy. In the EARS, high levels of rare earth elements (REE), Sr, Ba and Mg are expected in waters and solids in areas with alkaline volcanic rocks, while other critical elements, including helium, have been sought in other localities. The eastern and western branches of the EARS host juvenile sectors with promising geothermal potential related to hot fluids migrating along permeable faults.
The expedition began in the Virunga Volcanic Province in north-western Rwanda and continued all along Lake Kivu to Kamembe Further, along the Nyakabuye-Ruhwa Valley, in the area of Bugarama, Ruhwa and Mashyuza, gas, water, rock and sediment associated with natural hot springs but also cold springs were collected. On site, physical and chemical parameters were measured in-situ and documented together with the geology, infrastructure and domestic use of the hot site. At Ruhwa borehole, southern Rwanda, the hot water (66°C) emerges as an artesian spring at the surface. Drilling sites for geothermal water and energy extraction in Karisimbi were not visited because no economically viable geothermal system was found. Gisenyi and Bugarama are in the focus of the authorities, but funding for drilling at these sites was not yet achieved. We visited these sites to monitor the physicochemical parameters and to highlight the importance of their usage.
We strongly support the idea of using geothermal water in rural areas and decentralising the energy supply system to make it less prone to disruption. Since both geothermal sites, Gisenyi and Bugarama, are within highly populated areas, direct usage of heat and energy would be of major economic and ecologic advantage, saving wood and charcoal, preventing air contamination and providing energy for light and electric media in private and public properties. That said, there is huge potential to enhance the everyday life of local residence, making the society less prone to influences from outside their quarters, foreign countries and changing climate.
Ntihabose, Leon;Energy Development Corporation Ltd (EDCL), Kigali, Rwanda
Karangwa, Eugene;Energy Development Corporation Ltd (EDCL), Kigali, Rwanda
Stammeier, Jessica;GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
Zimmer, Martin;GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
Strauch, Bettina;GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
Niedermann, Samuel;GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
Regenspurg, Simona;GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
Contact
Wilke, Franziska D. H.
(Head of microprobe labs); GFZ Helmholtz Centre for Geosciences, Potsdam, Germany;
Contributors
Elements and Minerals of the Earth Laboratory (ElMiE Lab, GFZ German Research Centre for Geosciences, Germany); Microprobe Lab (GFZ German Research Centre for Geosciences, Germany); Gas Geochemistry Lab (GFZ German Research Centre for Geosciences, Germany); Noble Gas Lab (GFZ German Research Centre for Geosciences, Germany)
Funders
HORIZON EUROPE Climate, Energy and Mobility:
CRM-geothermal: Raw materials from geothermal fluids: occurrence, enrichment, extraction (101058163)
CharacterString: The East African Rift System (EARS) continues south of the Afar Crossing in Ethiopia through Kenya and then splits into two branches: the western branch, which runs through Uganda and Rwanda, and the eastern branch, which runs through Tanzania. Both unite in Malawi. Magmatic activity began 20 million years ago south of Lake Turkana (Kenya). Here, destabilisation of the continental lithosphere and extrusion of phonolitic floods occurred, and after a phase of resurgence, small-scale ultra-alkaline, Si-saturated activity took place between ca. 5.9 and 2.9 Ma, defining the early rift development and volcanic initiation phase. Volcanism in the western branch of the EARS is confined to four spatially restricted provinces, all of which are found at the tips of long boundary faults or in accommodation zones between rift segments (Ebinger et al., 1989).
In autumn 2024, an expedition to Rwanda was undertaken within the framework of the research project “CRM-geothermal”. Within „CRM-geothermal“, we are looking for an environmentally friendly co-production of critical raw materials together with the provision of geothermal energy. In the EARS, high levels of rare earth elements (REE), Sr, Ba and Mg are expected in waters and solids in areas with alkaline volcanic rocks, while other critical elements, including helium, have been sought in other localities. The eastern and western branches of the EARS host juvenile sectors with promising geothermal potential related to hot fluids migrating along permeable faults.
The expedition began in the Virunga Volcanic Province in north-western Rwanda and continued all along Lake Kivu to Kamembe Further, along the Nyakabuye-Ruhwa Valley, in the area of Bugarama, Ruhwa and Mashyuza, gas, water, rock and sediment associated with natural hot springs but also cold springs were collected. On site, physical and chemical parameters were measured in-situ and documented together with the geology, infrastructure and domestic use of the hot site. At Ruhwa borehole, southern Rwanda, the hot water (66°C) emerges as an artesian spring at the surface. Drilling sites for geothermal water and energy extraction in Karisimbi were not visited because no economically viable geothermal system was found. Gisenyi and Bugarama are in the focus of the authorities, but funding for drilling at these sites was not yet achieved. We visited these sites to monitor the physicochemical parameters and to highlight the importance of their usage.
We strongly support the idea of using geothermal water in rural areas and decentralising the energy supply system to make it less prone to disruption. Since both geothermal sites, Gisenyi and Bugarama, are within highly populated areas, direct usage of heat and energy would be of major economic and ecologic advantage, saving wood and charcoal, preventing air contamination and providing energy for light and electric media in private and public properties. That said, there is huge potential to enhance the everyday life of local residence, making the society less prone to influences from outside their quarters, foreign countries and changing climate.
pointOfContact
CI_ResponsibleParty
individualName
CharacterString: Wilke, Franziska D. H.
organisationName
CharacterString: GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
CharacterString: Study area in Rwanda East African Rift geothermal areas
geographicElement
EX_GeographicBoundingBox
westBoundLongitude
Decimal: 28.9985
eastBoundLongitude
Decimal: 29.6138
southBoundLatitude
Decimal: -2.65329
northBoundLatitude
Decimal: -1.40166
distributionInfo
MD_Distribution
transferOptions
MD_DigitalTransferOptions
onLine
CI_OnlineResource
linkage
URL: http://doi.org/10.5880/GFZ.DMJQ.2026.002
protocol
CharacterString: WWW:LINK-1.0-http--link
name
CharacterString: Data Access - DOI
description
CharacterString: Data Access - DOI
function
CI_OnLineFunctionCode (codeList=http://www.isotc211.org/2005/resources/Codelist/gmxCodelists.xml#CI_OnLineFunctionCode codeListValue=http://www.isotc211.org/2005/resources/Codelist/gmxCodelists.xml#CI_OnLineFunctionCode_information): information
Released
Dataset
Abstract
;GFZ Helmholtz Centre for Geosciences, Potsdam, Germany
Files
