blasthole stoping

Blasthole stoping is an underground mining method used for steeply dipping, strong ore bodies with regular boundaries and significant thickness. This technique involves creating a trough at the bottom of the ore body and a vertical slot extending across its width. Long blastholes are drilled from a level above, and blasting is conducted in successive slices, starting from the slot, to break down the ore.1

Variations include sublevel stoping, where shorter blastholes are drilled from intermediate levels, and vertical retreat mining, which uses a horizontal slot and blasts ore downwards. Techniques for extracting the broken ore from the trough bottom are employed after blasting. Shrinkage stoping is another method for steeply dipping, narrow ore bodies, where miners work off broken ore and blast new slices from the ceiling.12