offset vertical seismic profiling - ore-hosting calcareous siltstones
- opening
- opening driving
- opening due to crustal movement
- opening due to shrinkage
- opening location
- opening method
- opening of a deposit
- opening of discission
- opening of solution
- opening scheme
- opening slot
- opening-up by mine working
- opening-up of a mine
- opening-up of an opencast
- openlamp mine
- openness
- openwork
- operate round-year
- operating adit
- operating cash flow
- operating characteristic
- operating conditions
- operating expenses
- operating failure
- operating instructions
- operating level
- operating mine
- operating principle
- operating repair
- operation
- operation of producing
- operational depth
- operational exploration
- operational season
- operator
- operator cab
- operator prediction distance
- operator white noise level
- operculate
- operculum