By Desmond Subramani

South Deep Mine has some complex geology, it is located near Westonaria, around 50km from Johannesburg, South Africa. The mine is regarded as a “flagship ore reserve”, but it hasn’t always been that way. Historical complications and the complex nature of the location has meant years of work to understand the geology. Leapfrog Geo has been an important aspect in improving the geological models within the mine’s geological team. This post highlights some of the challenges and how Leapfrog Geo proved to be a useful solution.

The Geologists of South Deep and leapfrog gathered outside the offices at South Deep’s Twin Shaft.
The Geologists of South Deep and leapfrog gathered outside the offices at South Deep’s Twin Shaft.

The mining industry has continued to be severely affected by difficult economic conditions and various other factors causing a sense of unpredictability in the industry. Hendrick Pretorius, South Deep’s Chief evaluator, believes that a considerable number of mines in South Africa are still using rudimentary 2D geological modelling programmes for mine planning. Mining companies do not have to have complex geology to benefit from using 3D modelling technology like Leapfrog, even mines with simpler geology can benefit from incorporating it into their mining operations.

The challenges

  • The complexity of the alluvial deposit meant it was essential to have an accurate geological model.
  • The mine itself comprises of 16 reef horizons in a west-to-east fan formation that is up to 130m at its thickest and is highly faulted throughout.
  • Keeping the geological model update ahead of the production rate.
  • Remaining compliant to the mine plan.

For Deep South it was essential their geological model was continually up-to-date, to keep ahead of the production rate. So with the help of some in-house training provided by Leapfrog, geologists at South Deep equipped themselves with the knowledge to use Leapfrog Geo as an effective software tool. Leaving them an exciting opportunity to increase production effectiveness and reduce costs for South Deep.

No software customisations needed to be made to Leapfrog Geo for South Deep’s mine; all the design elements were capable of handling the mines complex geological modelling requirements. With Leapfrog Geo, a 3D model that closely resembles the realistic structure of a fault block can be produced. This ultimately makes the modelling process a far more dynamic and accurate one for geologists.

Some of the benefits for South Deep included:

  • The ability to build three complete faults in a day whereas previously even building one fault in a day was a challenge. Also the 3D model more accurately reflected the nature of faulting, producing a fault block with a volume that could be rotated to isolate individual faults in it, for closer analysis.
  • As new data becomes available Leapfrog Geo can dynamically update the model, compared to the digital terrain modelling programme that has to be completely reconfigured from scratch.
  • All data in the one place – having all data in Leapfrog makes everything more integrated, accessible and secure.

South Deep is an inspiring example of how Leapfrog Geo is helping to further mining companies to become more efficient, accurate and resourceful. Building a geological model more than three times faster than the digital terrain program can- now that’s a job well done!


Further reading:
Case Study – Can implicit modelling be used to model complex geology.