عنوان مقاله [English]
Ore reserves can be classified on the basis of various criteria. Geostatistical methods are highly accurate to estimate and classify ore reserves. The most important geostatistical methods to classify the ore reserves are number and quality of the data involved in estimation, error of Kriging variance and Kriging efficiency. In current research, the ore reserve of Robat-Arregijeh lead-zinc located in Khomein township in Markazi province, has been classified into three classes comprising proven, probable and prospected. In order to better recognizing the deposit and ore nature, first the strip log of all boreholes and 3-D lithology model of the region were drawn using Rockworks software. To estimate the ore reserve after variography of the region with SGeMS software, geostatistical ordinary block log-kriging method was used by DATAMINE software. By considering different economic conditions, average grade and amount of the ore reserve were estimated for cut off grade 1.5, 2 and 3 weighted percent. The comparison of the research results shows that amounts of reserves classified by the various methods are highly different. Number and quality of the data involved in estimation method with respect to the two others, yields higher value for proven reserve, with less accurate reversely. Therefore in practice these two methods are preferred in the first method. The amount of probable reserve of each three methods is close to each other.