Improvements on Estimation Tools and the Eff ect on Mineralisation Base Defi nition on the Zulti North Heavy Mineral Sand Deposit, Richards Bay, Kwa-Zulu Natal, South Africa

摘要

Richards Bay Minerals (RBM) has recently undertaken an exercise to improve orebody basalrndefi nition. Older mineralisation bases (pre-2005) were highly erratic using old protocol reverserncirculation (RC) (also known as Air Core) drilling and interpretation. The erratic nature of thisrnestimation tool, resulted in impractical modelling towards the end of mineralisation (EOM), diffi cultrnmine design and unrealistic reconciliation. New protocol drilling, which includes high defi nitionrnSONIC drilling data, has provided more data to be available for more accurate interpretation.rnRecent advances in drilling methodology has allowed for better penetration depths for SONICrndrilling, which was previously restricted to approximately 80 m (pre-2005). This improved datarnset allows more emphasis on geological interpretation with factors such as lithology, slime content,rnand mineral species distribution. These factors when in unique combination enable more accuraternand realistic EOM data points. These points are modelled into surfaces using conditional simulationrntechniques and result in a vastly smoother surface and consequently, a more representativernresource.