Abstract
This study uses exploration data to optimise overburden thickness, cut-off grade and stripping ratio at some alluvial gold mines in the Kibi mining district to improve gold recovery in Ghana. The specific objective is to determine sampling location, overburden thickness, gravel thickness, gravel grade and gold contents. Secondary data are from 48 mining blocks at Kwabeng mine and primary data from 20 mining blocks at Kibi goldfields. Data are analysed using basic statistics and binary plots. Gold content varies at constant total gravel section grade, as overburden thickness and gold grade vary at 0.2 m from 0 to 2.0 m and at 0.05 g/m3 from 0.10 to 0.65 g/m3, respectively. Average values of gravel thickness and gravel grade from both sites are 2.1 m and 0.57 g/m3, respectively. Percentage change in gold content only becomes positive after optimum overburden thickness and a cut-off grade of 0.90 m and 0.285 g/m3, respectively, while the stripping ratio is 0.43:1. The spatial plot of gravel grades using the Surfer Software for the Kwabeng deposit presents a unique resource block model. The optimised values can be used to review the resource block model and combining with established improved operational procedures from previous works.
Similar content being viewed by others
Abbreviations
- TSG:
-
Total section grade
- GSG:
-
Gravel section grade
- OS:
-
Overburden section
- DGS:
-
Diluted gravel sections
- GS:
-
Gravel section
- DF:
-
Dilution factor
- TS:
-
Total section
- g/m3 :
-
Grams per meter cube
- M:
-
Metre
- Oz:
-
Ounce (1 oz = 28.35 g)
- R 2 :
-
Coefficient of determination
- <:
-
Less than
- >:
-
Greater than
- o :
-
Initial quantity
- I :
-
Variable quantity
References
Abouchami W, Boher M, Michard A, Albarède F (1990) A major 2.1 Ga event of Mantle magmatism in West Africa: an early stage of crustal accretion. J Geophys Res 95:17605–17629. https://doi.org/10.1029/JB095iB11p17605
Akabzaa T (2000) Boom and dislocation: the environmental and social impacts of mining in the Wassa West District of Ghana. Third World Network, Accra 131p. https://www.worldcat.org/title/boom-and-dislocation-the-environmental-and-social-impacts-of-mining-in-the-wassa-west-district-of-ghana/oclc/49680055 (Accessed on 18 July 2020)
Anon (2009) Handbook for exploration and environmental geochemistry. Chapter 3: exploratory analysis of geochemical anomalies (In Geochemical Anomaly and Mineral Prospectivity Mapping in GIS; Edited by Emmanuel John M. Carranza) Vol. 11 p 51-84. https://doi.org/10.1016/S1874-2734(09)70015-4
Awudu GI (1994) A study of the mineral investment climate of Ghana: a project report submitted in partial fulfilment for Postgraduate (Professional) Diploma degree in Mining Engineering. http://hdl.handle.net/123456789/3445 (Accessed on 18 July 2020)
Bayari EE, Foli G, Gawu SKY (2019) Geochemical and pathfinder elements assessment in some mineralised regolith profiles in Bole-Nangodi gold belt in north-eastern Ghana. Environ Earth Sci 78:268. https://doi.org/10.1007/s12665-019-8265-5
Buadee NA, Gawu SKY, Foli G (2018) Assessing the occupational risks associated with artisanal and small-scale mining- a case study in Asankrangwa and Kenyasi areas in Ghana. West Afr J App Ecol 26(1):22–32 https://www.ajol.info/index.php/wajae/article/view/177599
Chudasama B, Porwal A, Kreuzer OP, Butera K (2016) Geology, geodynamics and orogenic gold prospectivity modelling of the Paleoproterozoic Kumasi Basin, Ghana, West Africa. Ore Geol Rev 78:692–711. https://doi.org/10.1016/j.oregeorev.2015.08.012
Clark I (2010) Statistics of geostatistics? Sampling error or nugget effect? J South Afr Inst Min Metall 83:187–198 https://www.saimm.co.za/Journal/v110n06p307.pdf
Dzigbodi-Adjimah K, Gawu SK (1994) Guides to Alluvial gold exploration in Ghana. Journal of Science and Technology 14(3)
George D, Mallery M (2010) SPSS for Windows step by step: a simple guide and reference, 17.0 update, 10a edn. Pearson, Boston
German K, Schwartz T, Wipki M (1994) Mineral Deposit Formation in Phanerozoic Sedimentary Basins of North-East Africa: The Contribution of Weathering. Geol Rundsch 83:187–198
Gravetter F, Wallnau L (2014) Essentials of statistics for the behavioral sciences, 8th edn. Wadsworth, Belmont
Griffis RJ, Barning K, Agezo FL, Akosah FK (2002) Gold deposits of Ghana. Minerals Commission Report, Accra, p 432
Griffith SV (1960) Alluvial prospecting and mining, Second Revised edn. Pergamon Press, New York, p 253
Kesse GO (1985) Rock and mineral resources of Ghana. A.A. Balkema, Amsterdam
Leube A, Hirdes W, Mauer R, Kesse GO (1990) The early Proterozoic Birimian Supergroup of Ghana and some aspects of its associated gold mineralisation. Precambrian Res 46:139–165. https://doi.org/10.1016/0301-9268(90)90070-7
Mboudou GMM, Fozao KF, Njoh OA, Agyingi CM (2017) Characterization of alluvial gold bearing sediments of Betare Oya District-East Cameroon, implication for gold exploration and recovery. Open J Geol 7:1724–1738. https://doi.org/10.4236/ojg.2017.711115
Oman PS (1977) A preliminary report details of the open pit mine model: Regional Copper-Nickel. Study Minnesota Environmental Quality Board. https://www.google.com/search?. Accessed 12 Jan 2019
Rae J, Agyemang K, Griffis RJ (2009) Technical Report on the Kibi Goldfields Mine Kwabeng Gold Project. CHEVYROCK ENGINEERING LLC, Naples https://www.xtragold.com/_resources/reports/2_3_1KibiGoldProject-TechnicalReport_NI-43-101.pdf. p34-43. Accessed 33 July 2020
Smith AJB, Henry G, Frost-Killian S (2016) A review of the Birimian Supergroup- and Tarkwaian Group-hosted gold deposits of Ghana. Episodes 39(2):177–197. https://doi.org/10.18814/epiiugs/2016/v39i2/95775
Thompson RJ (2005) Surface strip coal mining handbook. South African Colliery Manager Association (SACMA), Johannesburg Accessed 17 August 2020
Xingwana L (2016) Monitoring ore loss and dilution for mine-to-mill integration in deep gold mines: a survey-based investigation. South Afr J Min Metallurgy 116 pp. Accessed on 24 January 2019. https://doi.org/10.17159/2411-9717/2016/v116n2a6
Zyl DV, Sassoon M, Digby C, Fleury A.-M, Kyeyune S (2002) Mining for the future. Appendix A: the large volume of waste. Working paper. Mining, Minerals and Sustainable Development, No.31 https://pubs.iied.org/pdfs/G00560.pdf
Acknowledgements
The authors acknowledge the staff and management of the erstwhile, Kwabeng alluvial goldmine in Ghana, for making this data available for the research.
Author information
Authors and Affiliations
Corresponding author
Additional information
Responsible Editor: Murat Karakus
Rights and permissions
About this article
Cite this article
Foli, G., Agyemang, K., Brako, B.A. et al. Characterisation of alluvial gold exploration data to improve gold recovery in Ghana. Arab J Geosci 13, 1105 (2020). https://doi.org/10.1007/s12517-020-06073-4
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s12517-020-06073-4