Coaltech Research Association

Detection of Old Workings, Sinkholes, Underground Fires and Acid Mine Pollution Using Geophysics and Airborne Thermal Infrared Imagery

Michael van Schoor

Field trials at four collieries comparing ground and airborne geophysical methods, with case studies and an applications guideline for the Witbank and Highveld collieries.

by Michael van Schoor | March 2002

What this report found

Micro-gravity, electrical resistivity and time domain electromagnetics located the boundary between old workings and virgin ground, but no ground technique tested could resolve individual bords and pillars at the depths typical of the Witbank and Highveld coalfields. Airborne thermal infrared surveys worked well as a low cost regional reconnaissance tool for shallow sinkholes, fires and possible pollution plumes.

R1500,00

Description

Related Products

Markus Mathey

R Bergh

Development of Design Procedures for Long Slender Pillars

2005

Design guidance for rib pillars, built from back analysed in situ coal tests and two dimensional modelling rather than empirical data, for rock engineers laying out high extraction panels.

What this report foundNumerical modelling produced upper and lower bound strength formulae for rib pillars, the lower bound covering weak roof and floor contacts.

R1500,00

R1500,00

What this report found

Numerical modelling produced upper and lower bound strength formulae for rib pillars, the lower bound covering weak roof and floor contacts. The formulae apply between width to height ratios of 0.5 and 2.5, with linear interpolation below that, and give conservative designs above 3. Adjustments were suggested where regular joint sets occur.

Best Practice Guidelines for the Management of Spontaneous Combustion in Opencast Coal

G Stenzel

2024

Guidelines drawn from site testing at opencast coal operations, including trials of gypsum and fly ash sprays applied with a hydro seeder. For pit supervisors and mine safety staff.

What this report foundPractical guidance for opencast operations covers early detection with low cost thermal cameras, prevention, and the treatment methods in current use: water...

R1500,00

R1500,00

G Stenzel

What this report found

Practical guidance for opencast operations covers early detection with low cost thermal cameras, prevention, and the treatment methods in current use: water sprays and cannons, sand cladding of highwalls and stockpiles, removal of burning coal by dragline, tipping into water ponds and the treatment of sinkhole areas. A three month full scale trial of sprayed fly ash as an antioxidant is reported.

Shopping Basket