Shrinkage stoping is a vertical overhand stoping method in which most of the broken ore remains in the stope to provide a working floor for the miners. The broken ore also provides wall support until a stope is completed and ready for drawdown of the remaining ore.
In general, the method is used in steeply dipping (>50 dip) narrow ore bodies with regular boundaries. Ore and waste (both the hanging wall and the footwall) should be strong, and the ore should not be affected by storage in the stope. The method is labor intensive and cannot readily be mechanized. It is usually applied to ore bodies on narrow veins or to ore bodies for which other methods cannot be used or might be impractical or uneconomical.
The method can be easily applied to ore zones as narrow as 1 m (3.1 ft), but it can also be successfully used for extraction of much wider stopes. The method is most efficient when drilling of the ceiling or back is done with uppers instead of horizontally.
What’s a mining technique (modern or historical) that you find particularly clever in its use of natural forces? Share your thoughts!
Text rights: Peter Darling, 2011
Source: Society for Mining, Metallurgy, and Exploration.
