Calculation of time variations in mineral grades from high-resolution geostatistical models

Geostatistics provides us an effective and powerful tool to estimate ore grades. High resolution geostatistical models characterize the spatial variability of the orebody. It is often useful to predict the time variation of mineral grades prior to mining since the processing plant efficiency depends on the statistical behavior of the time variation of mining production before decision-making. A methodology is presented for this purpose.;Time variation depends on the mining sequence and rate. A Spatial-Temporal Modeling (STMOD) methodology, is developed to calculate the grade variation in a series of time intervals. It transforms variability from a spatial distribution to a time domain. Several examples are presented to demonstrate the algorithm and the associated program.;STMOD program has been developed to predict the time variation of studied mining process. The results for intermingled waste and ore must be evaluated on the basis of total mining rate. Furthermore, advanced applications, such as multiple mining faces have been explored with the proposed methodology.;A detailed case study using oil sands mining has been presented as an application of the STMOD methodology and program.