second phase - set of support
- secondary reaction
- secondary recovery
- secondary recovery method
- secondary reflection
- secondary relief
- secondary rib
- secondary rock pressure
- secondary rocks
- secondary schistosity
- secondary search rod
- secondary shot
- secondary stream
- secondary tectonite
- secondary tubercles
- secondary twinning
- secondary variations in depth
- secondary ventilation
- secondary wave
- secondary zonation
- secret dovetailling