Assessing structural challenges in potash mining: Perspectives from Yara solution mining, Dallol Depression, Northern Afar, Ethiopia

Mesele, Gebremariam; Hagos, Miruts; Konka, Bheemalingeswara; Gebreset, Tsegabrhan; Molla, Misgan; Cheepurupalli, N Rao; Hailu, Girmay; Debeb, Negassi; Hailesilasie, Assefa

doi:10.22044/jme.2025.15254.2921

Document Type : Original Research Paper

Authors

¹ Department of Geology., Adigrat University, Adigrat, Ethiopia

² School of Earth Sciences., Mekelle University, Mekelle, Ethiopia

³ School of Earth Sciences and Engineering., Botswana International University of Sciences and Technology, Private Bag16, Palapye, Botswana

⁴ Faculty of Mines, Aksum Institute of Technology., Aksum University, Ethiopia

⁵ School of Earth Sciences, Department of Geology., Samara University, Samara, Ethiopia

⁶ Department of Geology, Adigrat University, Adigrat, Ethiopia

https://doi.org/10.22044/jme.2025.15254.2921

Abstract

The Dallol Depression, located in the northern Danakil Depression, has a complex geological history shaped by Afar rifting, containing approximately 1.7 km of evaporite deposits. These deposits, heavily influenced by volcanic activity and extensional tectonic faulting, exhibit significant structural variability. This research focuses on the potash-bearing section of the salt sequence, which consists of several distinct layers including the marker bed, sylvinite member, upper carnallitite member, bischofitite member, lower carnallitite member, and kainitite member. Employing satellite imagery (Landsat Thematic Mapper), geological and structural mapping, borehole data, and seismic analysis, this study characterizes the sub-surface features of the evaporites and estimates their reserves. The RockWorks software facilitated the development of a subsurface stratigraphic map and a three-dimensional fence diagram for enhanced interpretation. Seismic data indicate that while the upper layers of the evaporite deposits are largely horizontal and undeformed, deeper layers exhibit considerable tectonic disturbance. Thickness variations were observed, with evaporite and alluvial deposits being thinner at the southeastern rim and thicker in the eastern concession center. The total potash reserve is estimated at approximately 2.96 billion tons, of which 877.76 million tons (29.60%) remain unexploited. Current borehole designs restrict the company's extraction capacity to 24.64%. This study recommends revising mining strategies, incorporating updated borehole designs and advanced geophysical methods to improve potash recovery and promote sustainable practices in the Dallol region.

Keywords

Main Subjects

Surface Mining

References

[1]. Hagos, M. (2011). Geochemical and Petrographic Studies of the Volcano-Tectonic Evolution of Northern Afar: Implications for the Structural Setup of the Actively Expanding Erta‟Ale Depression. PhD thesis, University of Vienna, Vienna, Austria, 239 p.

[2]. Tadesse, S., Milesi, J. P., & Deschamps, Y. (2003). Geology and mineral potential of Ethiopia: a note on geology and mineral map of Ethiopia. Journal of African Earth Sciences, 36(4), 273-313.

[3]. Tesfaye, S., Harding, D. J., & Kusky, T. M. (2003). Early continental breakup boundary and migration of the Afar triple junction, Ethiopia. Geological Society of America Bulletin, 115(9), 1053-1067.

[4]. Broughton, P. L. (2019). Economic geology of southern Saskatchewan potash mines. Ore Geology Reviews, 113, 103117.

[5]. Ushakova, Evgeniya, Anna Perevoshchikova, Elena Menshikova, Elena Khayrulina, Roman Perevoshchikov, and Pavel Belkin. (2023). "Environmental aspects of potash mining: a case study of the Verkhnekamskoe potash deposit." Mining, 3 (2), 176-204.

[6]. Ali, M. M., Petropoulos, S. A., Selim, D. A. F. H., Elbagory, M., Othman, M. M., Omara, A. E. D., & Mohamed, M. H. (2021). Plant growth, yield and quality of potato crop in relation to potassium fertilization. Agronomy, 11(4), 675.

[7]. Chen, W., Geng, Y., Hong, J., Yang, D., & Ma, X. (2018). Life cycle assessment of potash fertilizer production in China. Resources, Conservation and Recycling, 138, 238-245.

[8]. US Geological Survey. (2020). Mineral commodity summaries, US Geological Survey, 200 p.

[9]. Warren, J.K. (1999). Evaporites: their evolution and economics, Oxford, UK, Blackwell Scientific, 438 p.

[10]. Michon, L., Famin, V., & Quidelleur, X. (2022). Evolution of the East African Rift System from trap-scale to plate-scale rifting. Earth-Science Reviews, 231, 104089.

[11]. Girdler, R. W., Fairhead, J. D., Searle, R. C., & Sowerbutts, W. T. C. (1969). Evolution of rifting in Africa. Nature, 224(5225), 1178-1182.

[12]. Chorowicz, J. (2005). The east African rift system. Journal of African Earth Sciences, 43(1-3), 379-410.

[13]. Modisi, M. P., Atekwana, E. A., Kampunzu, A. B., & Ngwisanyi, T. H. (2000). Rift kinematics during the incipient stages of continental extension: Evidence from the nascent Okavango rift basin, northwest Botswana. Geology, 28(10), 939-942.

[14]. Kinabo, B. D., Atekwana, E. A., Hogan, J. P., Modisi, M. P., Wheaton, D. D., & Kampunzu, A. B. (2007). Early structural development of the Okavango rift zone, NW Botswana. Journal of African Earth Sciences, 48(2-3), 125-136.

[15]. Pastier, A. M., Dauteuil, O., Murray-Hudson, M., Moreau, F., Walpersdorf, A., & Makati, K. (2017). Is the Okavango Delta the terminus of the East African Rift System? Towards a new geodynamic model: Geodetic study and geophysical review. Tectonophysics, 712, 469-481.

[16]. Ebinger, C. J., Yemane, T., Woldegabriel, G., Aronson, J. L., & Walter, R. C. (1993). Late Eocene–Recent volcanism and faulting in the southern main Ethiopian rift. Journal of the Geological Society, 150(1), 99-108.

[17]. Ebinger, C. J., Deino, A. L., Tesha, A. L., Becker, T., & Ring, U. (1993). Tectonic controls on rift basin morphology: evolution of the Northern Malawi (Nyasa) Rift. Journal of Geophysical Research: Solid Earth, 98(B10), 17821-17836.

[18]. Beyene, A., & Abdelsalam, M. G. (2005). Tectonics of the Afar Depression: A review and synthesis. Journal of African Earth Sciences, 41(1-2), 41-59.

[19]. Corti, G. (2009). Continental rift evolution: from rift initiation to incipient break-up in the Main Ethiopian Rift, East Africa. Earth-science reviews, 96(1-2), 1-53.

[20]. Rime, V., Foubert, A., Ruch, J., & Kidane, T. (2023). Tectonostratigraphic evolution and significance of the Afar Depression. Earth-Science Reviews, 104519.

[21]. McKenzie, D. P., Davies, D., & Molnar, P. (1970). Plate tectonics of the Red Sea and east Africa. Nature, 226(5242), 243-248.

[22]. Barberi, F., Borsi, S., Ferrara, G., Marinelli, G., Santacroce, R., Tazieff, H., & Varet, J. (1972). Evolution of the Danakil Depression (Afar, Ethiopia) in light of radiometric age determinations. The Journal of Geology, 80(6), 720-729.

[23]. Ebinger, C. J., & Casey, M. (2001). Continental breakup in magmatic provinces: An Ethiopian example. Geology, 29(6), 527-530.

[24]. Acocella, V. (2010). Coupling volcanism and tectonics along divergent plate boundaries: Collapsed rifts from central Afar, Ethiopia. EGU General Assembly Bulletin, 122(9-10), 1717-1728.

[25]. McClusky, S., Reilinger, R., Ogubazghi, G., Amleson, A., Healeb, B., Vernant, P., & Kogan, L. (2010). Kinematics of the southern Red Sea–Afar Triple Junction and implications for plate dynamics. Geophysical Research Letters, 37(5).

[26]. CNR-CNRS (Afar Team). (1973). Geology of northern Afar (Ethiopia). Revue de Géographie Physique et de Géologie Dynamique, 15, 443–490.

[27]. Vereb, V., van Wyk de Vries, B., Hagos, M., & Karátson, D. (2020). Geoheritage and resilience of Dallol and the Northern Danakil Depression in Ethiopia. Geoheritage, 12, 1-34.

[28]. Wright, T. J., Ebinger, C., Biggs, J., Ayele, A., Yirgu, G., Keir, D., & Stork, A. (2006). Magma-maintained rift segmentation at continental rupture in the 2005 Afar dyking episode. Nature, 442(7100), 291-294.

[29]. Cavalazzi, B., Barbieri, R., Gómez, F., Capaccioni, B., Olsson-Francis, K., Pondrelli, M., & Hagos, M. (2019). The Dallol geothermal area, Northern Afar (Ethiopia)—An exceptional planetary field analog on Earth. Astrobiology, 19(4), 553-578.

[30]. Warren, J. K. (2016). Evaporites: A geological compendium. Springer.

[31]. Varet. J. (2018). Geology of Afar (East Africa), Springer International Publishing, Cham, Switzerland.

[32]. Allana Potash Corporation. (2011). Resource Report for the Danakhil Potash Deposit, Afar State Ethiopia, ERCOSPLAN Ingenieurgesellschaft (EGB 11-008), Germany.

[33]. Allana Potash Corporation. (2012). Dallol Potash Project— Draft Environmental, Social and Health Impact Assessment Report, Environmental Resources Management (ERM) (ERM Southern Africa Project 0143047), South Africa.

[34]. Warren, J. K. (2015). Danakhil Potash, Ethiopia: Is the present geology the key. SaltWork Consultants: Seacliff Park, Australia.

[35]. Holwerda, J. G., & Hutchinson, R. W. (1968). Potash-bearing evaporites in the Danakil area, Ethiopia. Economic Geology, 63(2), 124-150.

[36]. Warren, J. K. (2015). Danakhil potash, Ethiopia: Beds of kainite/carnallite, Part 2 of 4. Technical Report. Adelaide, SA: SaltWork Consultants Pte Ltd. doi: 10.13140/RG. 2.1. 2392.9769.

[37]. Barberi, F., Ferrara, G., Santacroce, R., & Varet, J. (1975). Structural evolution of the Afar triple junction. In Afar Depression of Ethiopia" E. Schweizerbart'sche Verlagsbuchhandlung, Vol. 1, pp. 38-54.

[38]. Wood Jr, G. H., Kehn, T. M., Carter, M. D., & Culbertson, W. C. (1983). Coal resource classification system of the US Geological Survey (No. 891). US Geological Survey.

[39]. Redfield, T. F., Wheeler, W. H., & Often, M. (2003). A kinematic model for the development of the Afar Depression and its paleogeographic implications. Earth and Planetary Science Letters, 216(3), 383-398.

Journal of Mining and Environment

Assessing structural challenges in potash mining: Perspectives from Yara solution mining, Dallol Depression, Northern Afar, Ethiopia

References

References

Volume 16, Issue 4
July and August 2025
Pages 1253-1268

Assessing structural challenges in potash mining: Perspectives from Yara solution mining, Dallol Depression, Northern Afar, Ethiopia

References

References

Volume 16, Issue 4July and August 2025Pages 1253-1268

Volume 16, Issue 4
July and August 2025
Pages 1253-1268