Resource estimation of the Damanghor gold deposit (Brdaskan, Northeast Iran) based on geological and grade continuity

The selection of an appropriate estimation method is a crucial decision in resource estimation processes. There are multiple resource estimation methods of which the most important one is block modelling. Among the block modelling methods used for the estimation of gold resources, three methods have a broader application. These methods include Inverse Distance Weighting (IDW), Ordinary Kriging (OK), and Full Indicator Kriging (FIK). We compared the results of these three techniques and selected the most appropriate method for resource estimation of the Damanghor gold deposit. For this purpose, we prepared the geometric model of the deposit based on geological continuity and then, conducted the variography procedure to determine the grade continuity and the amount of gold resource. The dataset of the Damanghor area included eight diamond drilling boreholes and eight exploratory trenches comprising the grade results of 405 samples. The results show that FIK is the best method for resource evaluation of this case study. The OK method, however, is not suitable for this deposit. The IDW method provides reliable results when the drilling spacing is less than the variography range. This results can be used for the estimation of inferred resources when the geological continuity is appropriately determined.