The spontaneous combustion index and its application: Past, present, and future
The Wits-Ehac index was developed in 1987 at the School of Mining Engineering, University of Witwatersrand. In this research, several tests were done for a colliery in the Waterberg coalfield using a Wits-Ehac index apparatus and were compared with the Glasser test. There was a good correlation between the two test types. Another data set was acquired from a risk assessment study of the Witbank coalfield using Geographical information Systems (GIS). This study used several types of data, including type of coal, overburden thickness, Wits-Ehac index, and chemical properties of coal. The research concluded that the Kleinkopje area is the most prone to spontaneous combustion, which agrees with historical observations. Improvements have been made on the apparatus that measures the Wits-Ehac index, with future applications highlighted. Because of increasing spontaneous combustion events in the Witbank coalfield, there is a need for more in-depth research about the process.
Figures & Tables
Geology of Coal Fires: Case Studies from Around the World
The “sedimentary cover” refers to the stratified rocks of youngest Proterozoic and Phanerozoic age that rest upon the largely crystalline basement rocks of the continental interior. The early chapters of the volume present data and interpretations of the geophysics of the craton and summarize, with sequential maps, the tectonic evolution of the craton. The main body of the text and accompanying plates and figures present the stratigraphy, structural history, and economic geology of specific sedimentary basins (e.g., Appalachian basin) and regions (e.g., Rocky Mountains). The volume concludes with a summary chapter in which the currently popular theories of cratonal tectonics are discussed and the unresolved questions are identified.