The empty or caved space left behind in an underground mine after the target coal or ore has been extracted. In longwall or room-and-pillar mining, the roof is often allowed to collapse into the goaf to relieve stress on the active working face.
Heard on the job
Keep an eye on the ventilation return near the goaf, we don't want methane building up in the bleeders.
Insider tip
Goaf is the traditional British and Australian spelling, while gob is more common in North America.
Also heard as
- gob
Related terms
Longwall
An underground coal mining method that extracts a wide panel in a single continuous slice.
Room and pillar
An underground mining method where material is extracted across a horizontal plane, leaving blocks of ore to support the roof.
Roof
The layer of rock located immediately above an underground excavation or mineral seam.