..., unfavourable stress field due to long-term mining). Destress blasting stages were carried out in a group of boreholes (4–8; diameter 95 mm) with the total explosive charge ranging from 2100 kg to 3750 kg, detonated regularly at a distance of 43 m to 114 m ahead of the advancing longwall face. Evaluation...

... (pump turbines) must be located considerably below the downstream water level, also calls for the construction of large underground powerhouses at great depth, which often exceeds 500 m. reservoir geomechanics borehole excavation granite principal stress Reservoir Characterization...

... for Geoscience, personal communication, 2015). stope borehole Upstream Oil & Gas Institute Reservoir Characterization Cooke Earthquake nakatani shaft durrheim mitigate seismic risk sensor reef metals & mining Witwatersrand basin southern african institute South Africa Research...

... or planned exploration or geological boreholes for seismic sensor placement is offered as a cost-effective solution to this problem. For existing mines planning to mine new, deeper ore zones, the ability to install seismic sensors in long boreholes is especially important where long ramps are being developed...

... of a vertical borehole (GT008) to a depth of 1 225 m was used to provide an indication of rock mass conditions within the shaft barrel and empirical shaft support design recommendations. Forty seven percussion boreholes surrounding the Shaft #1 position were drilled and grouted to a depth of 60 m to form...

... mechanics machine learning well logging orientation metals & mining Upstream Oil & Gas information log analysis classification mapping discontinuity rock mass contour rmr 89 rock mass quality model low rmr 89 borehole lineament interpretation structural domain plane rock mass...

... Organisation Hollow Inclusion cell) and the BXCCBO strain cell (BX-sized Compact Conical-ended Borehole Overcore cell) to measure in situ stress in Southern Africa. These two strain cells have proven their reliability, but stress measurements remain complex and the risk of measurement failure can be high...