A Preliminary Investigation Into the Geotechnical Interpretation of Geophysical Logs
Compares a full suite of downhole sondes against geotechnical core logging over the 5 m above three coal seams, for geologists and rock engineers assessing roof conditions.
by Lesley S Jeffrey | October 2004
Geophysical logging of boreholes above three Witbank seams identified clay rich matrices, stiffness changes, bedding planes and the principal stress direction, and picked up fractures in 30 to 75 per cent of cases. Core logging found most of the same features faster, so routine use was not recommended unless stiffness and stress direction matter.
R1500,00
Description
Related Products
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.
R1500,00
Dolerites in the study area differ in mineral content, geometry, thickness, grain size and degree of alteration. Plagioclase textures indicate fractionation at different depths in the crust for the Witbank and Sasolburg intrusions, and the olivine content points to separate magma sources for two of the sills. Fine crystalline dolerite, including chilled margins and bifurcations, alters most readily.
A technology to condition plants with adapted Rhizospheric soil/substrate bacterial species to improve vegetation resilience and growth on rehabilitated land
2024
Review and proposed method for using soil microbial communities to establish lasting vegetation on coal waste substrates where topsoil is scarce. For rehabilitation and closure practitioners.
What this report foundConventional rehabilitation relies on lime, fertiliser and compost to build fertility and select adaptive species, which produces short term cover but rarely a...
R1500,00
Conventional rehabilitation relies on lime, fertiliser and compost to build fertility and select adaptive species, which produces short term cover but rarely a self sustaining ecosystem. The work argues for treating soil microbes as part of the system, since bacteria drive nutrient cycling, organic matter breakdown and soil aggregation, and proposes conditioning plants with adapted rhizosphere bacteria on coal waste substrates.
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...
R1500,00
Testing 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 self-heat and pyrite in them speeds the process. Higher carbon, moisture, hydrogen, volatile matter and nitrogen with lower ash all raised proneness to self-heating, so proximate and ultimate analysis can serve as a screening tool.