Assessments of Rock Fall and Joint Failure Risk in ‎A Geologically Complex Section, South Cut 8 Area, ‎DK2 Jwaneng Pit, Botswana

  • Authors

    • Morwaake Brian Ntehelang Department of Mineral Resources, Botswana International University of Science & Technology
    • Rahul Verma Department of Mineral Resources, Botswana International University of Science & Technology
    • Yendaw Department of Mineral Resources, Botswana International University of Science & Technology
    • Jerome Anabannye Department of Mineral Resources, Botswana International University of Science & Technology
    https://doi.org/10.14419/fwq0t273

    Received date: May 26, 2025

    Accepted date: June 5, 2025

    Published date: July 6, 2025

  • Cut 8; Joints; DIPS; RS2; Slope Reinforcement; Dewatering

  • Abstract

    Jwaneng Mine is one of the richest diamond mines in the world. This mine is the ‎flagship of Debswana due to the substantially higher dollar per carat obtained for its gems. ‎Jwaneng Mine contributes about 60-70% of Debswana’s total revenue. Currently, Jwaneng ‎is mining at a depth of 452 metres and is expected to reach 816 metres by 2034. The ‎Jwaneng kimberlites are emplaced in a thick sequence of shales, sandstones, and dolomites ‎of the Kalahari Formation, with thin occurrences of mudstones and siltstones in areas. The ‎Jwaneng Mine exploits a diamond-bearing Kimberlite complex of three main pipes known ‎as the DK2 Kimberlite. The mine is currently being expanded through the Cut 9 ‎underground project. The deepening and widening of the pit have introduced complicated ‎geotechnical issues, particularly on the southern side of the excavation. The steep rock ‎slopes and the presence of primary & secondary discontinuities, such as joints, bedding ‎planes, and faults, heighten the risk of rockfall and structural failure, are significant threat ‎to personnel safety, operational efficiency, and equipment integrity. The present work aims ‎at a thorough and focused study of the evaluation of potential rock failure modes in the Cut 8 ‎South region and for developing effective monitoring and mitigation strategies to ensure ‎safe mining operations. Data obtained through geological and structural mapping of the Cut ‎‎8 South side was used to identify key discontinuities, including joint sets, faults, and ‎bedding planes. Kinematic analysis using stereographic projection was done to assess ‎potential failure modes such as planar, wedge, and toppling failures. Further, slope stability ‎modelling was done to simulate potential failure scenarios under existing conditions. Both ‎DIPS and RS2 confirm that the wedge failures were common in areas with high joint ‎density. Controlled blasting methods were recommended to reduce the effects of vibration ‎on joined rock masses. Another recommendation is the slope reinforcement through ‎structural support via the targeted placement of shotcrete, wire mesh, and rock bolts in ‎high-risk areas. Lastly the efficient water management is necessary to regulate pore ‎pressures. Draining out thorough dewatering wells and horizontal drains must be set up‎.

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  • How to Cite

    Ntehelang , M. B. ., Verma, R. ., Yendaw, & Anabannye , J. . (2025). Assessments of Rock Fall and Joint Failure Risk in ‎A Geologically Complex Section, South Cut 8 Area, ‎DK2 Jwaneng Pit, Botswana. International Journal of Basic and Applied Sciences, 14(2), 634-644. https://doi.org/10.14419/fwq0t273