Colliston, W. P.Victor, Gerhard2017-03-162017-03-162016-01http://hdl.handle.net/11660/5885enWitwatersrand BasinWelkom (Free State -)Welkom GoldfieldWelkom FormationUF1 – Zone 2Tunnel Failure (-Collapse)Gold mines and mining -- South Africa-- Free StateTunnelingRock mechanicsRock deformationMine safetyDissertation (M.Sc. (Geology))--University of the Free State, 2016DissertationUniversity of the Free State