To intentionally collapse the roof of an underground excavation by removing the supporting pillars or blasting the overhead rock. This controlled failure allows miners to extract the remaining ore from the pillars or draw broken ore down from a massive deposit above.
Heard on the job
Once we pull the last of the coal from this panel, we'll pull the props and let the roof cave behind us.
Related terms
Goaf
The empty or caved space left behind in an underground mine after extraction.
Depillar
To extract the supporting columns of ore or coal left behind during initial mining.
Room and pillar
An underground mining method where material is extracted across a horizontal plane, leaving blocks of ore to support the roof.