Professor Nikki Wagner
Department of Geology
University of Johannesburg, Johannesburg, South Africa. / 011 559 4719 / 082 8539780

Research keywords: organic petrology; coal petrography; trace elements in coal; coal geology; carbon dioxide capture and storage; coal oxidation; underground coal gasification; coal conversion; coal ash; vitrinite reflectance for thermal maturity determination.

Prof Wagner was inaugurated as a Professor in Geology at the University of Johannesburg in 2021, and was elected as Fellow of the Geological Society of South African in 2020. Nikki completed her Phd in 1999, and shortly thereafter worked for Sasol in their Coal to Syngas Research Group, where her interest in trace elements in coal developed. Dr Wagner worked for Sasol for 6 years, before joining the School of Chemical and Metallurgical Engineering at the University of the Witwatersrand, Johannesburg, where she ran the Coal Research group for 8 years before moving back into geology at the University of Johannesburg in 2014. Prof Wagner has over 75 publications listed in Scopus, and has supervised over 35 postgraduate students at UJ and Wits. Prof Wagner specializes in organic petrology, and is able to provide an analytical service to industry, parastatals, and tertiary institutions on coal, carbon, shale gas, coal ash, and so on.

Pertinent publications

Book: Nicola Wagner, Nandi Malumbazo and Rosemary Falcon. (2018) Southern African Coals and Carbon. Struik Nature, Cape Town, 248pp.

Publications since 2020:

  1. Mavhengere, P., Wagner, N., Bada S., Malumbazo, N. (2021). Physical and structural changes in the Zululand Basin (South Africa) Cenomanian Sandstone Core sample associated with long term supercritical CO2 and SO2 Journal of African Earth Sciences (under review).
  2. Mavhengere, P., Wagner, N., Malumbazo, N. 2021. The Effects of Long-Term Supercritical CO2 Exposure on Zululand Basin Core Samples. Energy (accepted Jan 2021).
  3. Wagner, Geology of Coal, 2021. In: Alderton, David; Elias, Scott A. (eds.) Encyclopedia of Geology, 2nd edition, vol.[5], pp. 745-761. United Kingdom: Academic Press.
  4. Ahmed, U, Wagner N.J., Joubert, A. Quantification of radionuclides and associated radiological risk estimation of coal combustion residues from a South African coal-fired power plant. International Journal of Radiation Research, vol 19-1 (in print)
  5. Wagner, N.J., Mokwena, M.L., Kolker, A. Occurrence and probable source of chromium enrichment in Permian coals, South Africa. South African Journal of geology. (in print)
  6. Hower, J., Rimmer, S.M., Mastalerz, M., Wagner N.J. 2021. Migmatite-like textures in anthracite: Further evidence for low-grade metamorphic melting and resolidification in high-rank. Geoscience Frontiers. (in print Jan 2021)
  7. Badenhorst, C.J., Santos C., Lázaro-Martínez, J., Białecka, B., Cruceru, M., Guedes, A.,Guimarães, R., Moreira, K., Predeanu, G., Suárez-Ruíz, I., Cameán, I., Valentim, B., Wagner, N. 2020. Assessment of Graphitized Coal Ash Char Concentrates as a Potential Synthetic Graphite Source. Minerals 10, 986. (1 cit)
  8. Baiyegunhi,Kuiwu, T.L., Gwavava, L.O., Wagner, N., Baiyegunhi, C. 2020. Geochemical Evaluation of the Cretaceous Mudrocks and Sandstones (Wackes) in the Southern Bredasdorp Basin, Offshore South Africa: Implications for Hydrocarbon Potential. Minerals 10, 595
  9. Chabalala, V., Wagner, N, Malumbazo, N., Eble, C. Geochemistry and Organic Petrology of the Permian Whitehill Formation, Karoo Basin (RSA) and the Devonian/Carboniferous shale of the Appalachian Basin (USA). International Journal of Coal Geology 103612
  10. Ahmed, U, Wagner N.J., Joubert, A., Quantification of U, Th and specific radionuclides in coal from selected coal fired power plants in South Africa. PLOS ONE 15:5: e0229452.1-9
  11. Mosele M. Tsemane, Ratale H. Matjie, John R. Bunt, Hein W.J.P. Neomagus, Christien A. Strydom, Frans B. Waanders, Wagner N.J., Hoffman J.W. Significance of coal properties on the caking degree of coarse coal particles mined at Limpopo Province, Republic of South Africa.International Journal of Coal Preparation and Utilization, 40 (4-5), 297-319. DOI: 10.1080/19392699.2020.1722657
  12. Misz-Kennan,⁎, J. Kusb, D. Floresc, C. Avilad, Z. Buckune, N. Choudhuryf, K. Christanisg, J.P. Jouberth, S. Kalaitzidisg, A.I. Karayigiti, M. Malechaa, M. Marquesc, P. Martizzij, J.M.K. O’Keefek, W. Pickell, G. Predeanum, S. Puszn, J. Ribeiroo,v, S. Rodriguesp, A.K. Singhq, Suarez-Ruizr, I. Sykorovas, N.J. Wagner, D. Životiću, ICCP. 2020. Development of a petrographic classification system for organic particles affected by self-heating in coal waste. (An ICCP Classification System, Selfheating Working Group – Commission III). International Journal of Coal Geology220, 103411 (2 cits).
  13. Hackley, P., Araujo, C.V., Borrego A.G…… Wagner, N.J. (42 authors listed alphabetically). 2020. Testing reproducibility of vitrinite and solid bitumen reflectance measurements in North American unconventional source-rock reservoir petroleum systems. Marine and Petroleum Geology 114 104172. (3 cit)