A Methodology for Calculating Tonnage Uncertainty in Vein-Type Deposits

Abstract

One of the main sources of uncertainty in vein type deposits is found in the calculation of the tonnage. The boundary limits often applied to a vein type deposit are calculated from sparse data using deterministic methods that offer no measure of uncertainty. The most common method used to calculate the tonnage of a vein-type deposit is to convert the volume of the deposit defined by a wireframe model into a tonnage. Wireframe models are deterministic, created from the interpretation of level plans and cross sections. These types of models have no provision for the calculation of tonnage uncertainty. One method of calculating the tonnage uncertainty in vein deposits is through the use of a distance function. This thesis presents a distance function (DF) approach that allows for the introduction of uncertainty into the modeling process by defining a zone or bandwidth that is quantifiable.