Application of sedimentology to the geostatistical modelling of the gold deposit at Iduapriem, Ghana

At Iduapriem Gold Mine, the blast holes used for sampling are parallel to the gold bearing sedimentary strata, which is not conducive to good grade control. However, the distribution of the gold is related to a variety of sedimentary parameters. These parameters were used to develop a sedimentary model, which divides the Banket into units that possess marked variations in mean grade and variance from each other. By estimating the position of the unit contacts, better grade control can be achieved through calculating the grade of a sampling block by weighting the samples with the proportion of each unit in that sampling block. The calculated grade of the sampling blocks can then be used to produce more accurate grade estimates of the mining blocks.