Structural and Hydrogeological Characterization of the Olkaria Dome Geothermal Field, Lake Naivasha Basin

Year : 2026 | Volume : 13 | Issue : 02 | Page : 28 49
By

Bernard Kipsang Rop,

  1. , PhD Scholar (MGSK, Reg. Geol., NEMA Expert) Department of Mining, Materials and Petroleum Engineering, Jomo Kenyatta University of Agriculture and Technology Kenya, Nairobi, ,

Abstract

The Olkaria Dome Geothermal Field in the Lake Naivasha Basin is one of Kenya’s principal geothermal resource areas, where fluid circulation and reservoir performance are strongly controlled by geological structures and hydrogeological conditions. This study integrates geological, structural, hydrogeological, mineralogical, and soil-gas data to characterize reservoir permeability and fluid flow pathways. Correlation of lithological units with drilling circulation-loss zones identifies highly fractured formations that enhance geothermal fluid movement. Mineralogical mapping delineates hydrothermal alteration associated with fluid–rock interaction, while soil-gas surveys using radon and carbon dioxide reveal fault-controlled permeable zones and subsurface connectivity within the geothermal system. The results demonstrate that structural controls significantly influence geothermal fluid circulation and reservoir behavior. These findings provide a basis for improved reservoir management, well targeting, and sustainable geothermal resource development in the Olkaria Dome Geothermal Field.

Keywords: Olkaria dome geothermal field, Lake Naivasha basin, geothermal exploration, structural geology, hydrogeology, reservoir permeability, soil-gas geochemistry

[This article belongs to Journal of Geotechnical Engineering ]

How to cite this article: Bernard Kipsang Rop. Structural and Hydrogeological Characterization of the Olkaria Dome Geothermal Field, Lake Naivasha Basin. Journal of Geotechnical Engineering. 2026; 13(02):28-49.
How to cite this URL: Bernard Kipsang Rop. Structural and Hydrogeological Characterization of the Olkaria Dome Geothermal Field, Lake Naivasha Basin. Journal of Geotechnical Engineering. 2026; 13(02):28-49. Available from: https://journals.stmjournals.com/joge/article=2026/view=258220

References

  1. Achini HN, Adeigbe OC, Rop BK. Characterizing permeability from geological and geochemical data in the Olkaria Domes Field in Kenya. East Afr J Environ Nat Resour. 2021;3(1):161-82. doi:10.37284/eajenr.3.1.429.
  2. Fleury P, Bakalowicz M, de Marsily G, Cortes JM. Functioning of a coastal karstic system with a submarine outlet, in southern Spain. Hydrogeol J. 2008;16:75-85. doi:10.1007/s10040-007-0215-8.
  3. Baker HB. Geology of the Olkaria geothermal field. Geothermics. 2024;101624. doi:10.1016/j.geothermics.2024.101624.
  4. Bignall G, et al. The geology and geothermal potential of the Olkaria area, Kenya. Geothermics. 2000;29:257-76. doi:10.1016/S0375-6505(00)00006-5.
  5. Burnside NM, Montcoudiol N, Boyce AJ. Surface and groundwater hydrochemistry in the mid-Gregory Rift, Kenya: first impressions and potential implications for geothermal systems. E3S Web Conf. 2019;98:07004. doi:10.1051/e3sconf/20199807004.
  6. Chorowicz J. The East African rift system. J Afr Earth Sci. 2005;43:379-410. doi:10.1016/j.jafrearsci.2005.07.019.
  7. Clarke J, et al. The geology of the Lake Naivasha Basin, Kenya. J Afr Earth Sci. 1990;10(1):1-12. doi:10.1016/0899-5362(90)90002-4.
  8. Darling WG, et al. The use of stable isotopes in the study of geothermal systems: a case study from the Olkaria geothermal field, Kenya. Geothermics. 1996;25:1-20. doi:10.1016/0375-6505(95)00029-5.
  9. Davis PM, Slack PD. The uppermost mantle beneath the Kenya dome and relation to melting, rifting and uplift in East Africa. Geophys Res Lett. 2002;29(7):1117. doi:10.1029/2001GL013676.
  10. Hackman BD, Charsley TJ, Kagasi J, Key RM, Siambi WS, Wilkinson AF. Geology of Isiolo Area. Report No. 103. Republic of Kenya: Mines and Geological Department; 1989.
  11. Kamau M, Hecker C, Lievens C. Use of short-wave infrared reflectance spectroscopy to characterize hydrothermal alteration minerals in Olkaria geothermal system, Kenya. In: Stanford Geothermal Workshop. Stanford: Stanford University; 2020. Available from: pangea.stanford.edu.
  12. Karingithi C. Hydrothermal alteration and mineralization in the Olkaria geothermal field, Kenya. Geothermics. 2009;38(1):72-9. doi:10.1016/j.geothermics.2008.10.001.
  13. Karingithi CW. Hydrothermal alteration and mineralization in the Olkaria geothermal field, Kenya. J Volcanol Geotherm Res. 2020;392:106120. doi:10.1016/j.jvolgeores.2020.106120.
  14. Key RM, Rop BK, Rundle CC. Geology of the Marsabit Area: Report 108. Reconnaissance. Nairobi, Kenya: Ministry of the Environment and Natural Resources, Mines and Geological Departments; 1987. 42 p.
  15. Link K, Koehn D, Barth MG, Tiberindwa JV, Barifaijo E, Aanyu K, et al. Continuous cratonic crust between the Congo and Tanzania blocks in western Uganda. Int J Earth Sci. 2010;99:1559-73. doi:10.1007/s00531-010-0548-8.
  16. Lagat JK. Geology: Hydrothermal Alteration and Fluid Inclusion Studies of the Olkaria Domes Geothermal Field [master’s thesis]. Iceland: University of Iceland; 2004.
  17. Chardot L, Jolly AD, Kennedy BM, Fournier N, Sherburn S. Using volcanic tremor for eruption forecasting at White Island volcano (Whakaari), New Zealand. J Volcanol Geotherm Res. 2015;302:11-23. doi:10.1016/j.jvolgeores.2015.06.001.
  18. Mwania MM. Evaluation of subsurface structures using hydrothermal alteration mineralogy—a case study of Olkaria South East field. GRC Trans. 2015;39.
  19. Rop BK, Mwanganga FR, Kiprotich KP. Evolutionary dynamics of the East African Rift System: implications for hydrocarbon exploration. J Geotech Eng. 2023;9:1-17.
  20. Rop BK. Stratigraphic and Sedimentological Study of Mesozoic–Tertiary Strata in Loiyangalani Area, Lake Turkana District, NW Kenya [dissertation]. Windsor, Canada: University of Windsor; 1990. 146 p. Paper 3602. ISBN 0-315-61857-4.
  21. Kwelwa SD, Sanislav IV, Dirks PHGM, Blenkinsop T, Kolling SL. Zircon U-Pb ages and Hf isotope data from the Kukuluma Terrain of the Geita Greenstone Belt, Tanzania Craton: implications for stratigraphy, crustal growth and timing of gold mineralization. J Afr Earth Sci. 2018;139:38-54. doi:10.1016/j.jafrearsci.2017.11.027.
  22. Smith MC. A history of hot dry rock geothermal energy systems. J Volcanol Geotherm Res. 1983;15:1-20. doi:10.1016/0377-0273(83)90093-8.
  23. Warega J. Geothermal prospecting of Olkaria Dome areas in Naivasha, Nakuru County, Kenya using gravity method. J Earth Environ Sci. 2020;12(4):45-58. doi:10.15406/jees.2020.12.0045.
Regular Issue Subscription Original Research
Volume 13
Issue 02
Received 23/06/2026
Accepted 02/07/2026
Published 12/07/2026
Publication Time 19 Days

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