Geology and Geophysics
Coal Washability Using Coal Petrography
2019
Summary of postgraduate work validating washability prediction for southern African coals by image analysis and tomography, written for geologists, metallurgists and mining engineers valuing a deposit.
What this report foundA single float sink test destroys the sample and gives one deterministic answer, so it cannot show how washability changes with particle size distribution.
Collation of Historic Thermal Imagery
2008
Pilot exercise pulling scattered thermal survey datasets held by companies and research bodies into one mapping system, with a view to tracking coal fires and mine water discharge.
What this report foundExisting thermal imagery of the Witbank coalfield was traced to its holders and assessed for format, quality, resolution and coverage, then brought into one...
Create Sedimentological and Structural Models to Assist in Identifying Geological Features That Impact on Mining
2001
Regional geology mapped in three dimensions from borehole data supplied by three mining groups, built for mine geologists and planners assessing seam disruption before layout design.
What this report foundA three dimensional model of the northern Witbank and Highveld coalfield was built from more than 1100 borehole logs, with strata sorted into 13 major...
Detection of Old Workings
2008
Review of earlier geophysical work plus literature, setting out method selection and test site requirements ahead of field trials, for engineers assessing undermined ground before development.
What this report foundMicrogravity, resistivity based methods including self potential, and time domain electromagnetics are identified as able to detect and delineate shallow old...
Detection of Old Workings, Sinkholes, Underground Fires and Acid Mine Pollution Using Geophysics and Airborne Thermal Infrared Imagery
2002
Field trials at four collieries comparing ground and airborne geophysical methods, with case studies and an applications guideline for the Witbank and Highveld collieries.
What this report foundMicro-gravity, electrical resistivity and time domain electromagnetics located the boundary between old workings and virgin ground, but no ground technique...
Economic Coal Resources of the Highveld, Ermelo, South Rand and Sasolburg-vereeniging Coalfields
2004
Comparative ranking of coalfields inside and outside South Africa on exploration level, resource size and infrastructure, for companies deciding where to explore next.
What this report foundA rating and ranking system was applied to South African coalfields and, separately, to the coal bearing countries elsewhere in the Southern African...
Evaluate the Remaining Resources of Low Phosphorus Coal in Mpumalanga Province
2004
Assessment of remaining metallurgical grade coal in the Witbank, Highveld and Ermelo coalfields from national borehole records, for resource planners and buyers of reductant coal.
What this report foundTonnage estimates for the remaining low phosphorus resource could not be produced, because the phosphorus analyses supplied by mining companies did not state...
Evaluation of Ground Geophysical Techniques on the Waterberg Coal Fields
2008
Interim account of trial ground surveys along a profile in the Waterberg coalfield, for exploration geologists weighing survey cost against the structural detail mine planning needs.
What this report foundElectrical and electromagnetic ground surveys were run over a Waterberg profile with borehole logs and three dimensional seismic data as control, to test...
Geotechnical Factors Associated With Previously Mined Areas of Coal and Their Impact on Subsequent Extraction
2002
Masters research on pillar extraction in the Witbank Coalfield, ranking the ground conditions that decide method choice and safety, for rock engineers and mine planners.
What this report foundGeotechnical factors affecting secondary extraction were identified from interviews with collieries already re-mining pillars and with people experienced in...
Identify Remnant Coal Deposits for Potential Exploitation by Small Business Developments
2002
Screening of near surface remnant coal for small scale miners in Mpumalanga, with a map of candidate areas and of ground already worked out.
What this report foundShallow coal suitable for small scale opencast working was mapped in the northern Witbank and Highveld coalfields, using a limit of 30 m from surface to the...
Intra-seam Sedimentological Controls on Coal Quality: 2 Seam, Witbank Coalfield
2003
Sub-seam mapping at an opencast colliery in the Witbank area, setting out a method geologists and resource estimators can apply to other seams.
What this report foundSub-seams within the No 2 Seam were characterised at a single test site using lithology, seam thickness, proximate analysis, petrography and geophysical logs...
Multi-client Aeromagnetic Data Merge & Interpretation – Witbank Coalfield
2005
Merged magnetic coverage and dyke interpretation across most Witbank mining and exploration ground, delivered as maps and GIS files for geologists planning around intrusions.
What this report foundGovernment and industry aeromagnetic data over the Witbank Coalfield were merged into one set of maps and GIS compatible files, and roughly 1200 dyke traces...
Petrochemical Characterization of Dolerites and Their Influence on Coal in the Witbank Highveld Coalfield, South Arica
2008
Masters study of dyke and sill intrusions at collieries in the Witbank and Highveld coalfields, using thin section petrography and X-ray fluorescence, for exploration geologists.
What this report foundDolerites in the study area differ in mineral content, geometry, thickness, grain size and degree of alteration.
Spontaneous Combustion of Coal and Coal-shales
2018
Laboratory testing of samples from South African collieries using two Wits self-heating indices alongside proximate and ultimate analysis, for ventilation and safety engineers assessing burning shale risk.
What this report foundTesting of 28 coal and coal-shale samples showed the coals to be more liable to spontaneous combustion than the shales, though reactive coal-shales still...