Projects THE BASIL READ GROUP Mining and processing activities in Zimbabwe and some thoughts on mining the Great Dyke. Dr Michael Roberts, TWP SAIMM Zimbabwe Branch May 2010
Who are we? Basil Read Construction Buildings Roads Civils MiningDevelopmentsEngineering Basil Read Engineering TWP
Who are we?
A generic description of some project work undertaken in Zimbabwe by TWP. What do we do?
Pickstone-Peerless hydrothermal gold deposits. Activity
Location
Pickstone-Peerless hydrothermal gold deposits. A plant will be built on site to treat a sulphide dump. Later there might be consideration given to going underground. Activity
Unki declines on the Great Dyke. Activity
Unki declines on the Great Dyke. Declines completed. Activity
Evaluating and assisting with respect to efficient Chrome mining associated with the Great Dyke.
Activity Optimise mining and process engineering on the Great dyke with respect to Platinum group elements. How done. Optimise mineralogy, mining and process engineering by recognising that the ore body is not homogeneous.
The Bushveld complex
The Great dyke
There might be some commonality with respect to structure in the Bushveld and the Great Dyke. Mining on the Bushveld and Great dyke
Easy mining on the Great Dyke
Easy mining on the great dyke
Easy mining on the Great Dyke
Easy mining on the Bushveld
Difficult mining on the great dyke
Difficult mining in the Bushveld
Some commonality with respect to structure in the Bushveld and the Great Dyke. Flexural slip thrust faults. Great dyke
Flexural slip thrust fault
What is a flexural slip thrust fault? Ore body Section Flexural slip thrust fault Flat Ramp
Flexural slip thrust fault Flat Ramp
Flexural slip thrust fault on the Great Dyke ?????
Flexural slip thrust fault - origins
Flexural slip thrust fault - origin
Scientific description of a flexural slip thrust fault Part of the Platmine Research Programme funded by: Anglo Platinum Impala Platinum Lonmin Peer reviewed scientific paper referenced: S. Perritt and M.K.C. Roberts “Flexural-slip structures in the Bushveld Complex, South Africa?” Journal of Structural Geology, Volume 29, Issue 9, September 2007, Pages S. Perritt and M.K.C. Roberts “Flexural-slip structures in the Bushveld Complex, South Africa?” Journal of Structural Geology, Volume 29, Issue 9, September 2007, Pages
Fall of ground fatalities over a set period Curved joint moved as a precursor to fall of ground Thrust fault or curved joint directly fell on deceased Seismic causes Other reasons for fall of ground 9/3215/322/326/32 Breakdown as to cause of 32 fall of ground fatalities
Pillar failure due to gouge on flexural slip thrust fault
Gouge
Pillar failure due to gouge on flexural slip thrust fault
Understanding the structures Understanding geological structures within the ore body. Rock mass ratings. Rock strengths Mining method. Appropriate mining span Excavation support Structural geology Rock engineeringMining engineering Knowledge gap
Understanding the structures Understanding geological structures within the ore body. Rock mass ratings. Rock strengths Mining method. Appropriate mining span Excavation support Structural geology Rock engineeringMining engineering Knowledge gap Expect surprises and production disruptions
Understanding the structures Understanding geological structures within the ore body. Rock mass ratings. Rock strengths Mining method. Appropriate mining span Excavation support Structural geology Rock engineeringMining engineering Expect smoother production profile No knowledge gap
TWP Plant Design Example
Thank you