RESOURCE MODELLING AT THE ILOVICA-ŠTUKA PORPHYRY COPPER-GOLD DEPOSIT, EASTERN MACEDONIA

Abstract

The Ilovica-Štuka porphyry system is located in southeast Macedonia, within the Tertiary belt associated with tectonic accretion along the western Tethyan belt. The intrusive is about 1.5 km in diameter and comprises a dacite-granodiorite plug, emplaced along the northeastern border of the Strumica graben. Mineralization is typical porphyry style veining, most intense within the potassic zone. The mineralization shows good continuity and homogeneity that lends itself well to bulk-mining methods. Modelling and estimation has been completed using Geovia Surpac. Exploratory data analysis highlighted a number of statistically differentiated grade populations, which were interpreted to be controlled by the following: alteration style, lithology, oxidation state elevation and stockwork intensity. Statistical and grade continuity analyses were completed to characterize the mineralization and subsequently used to develop grade interpolation parameters. Grade estimation was completed using ordinary kriging. The search ellipsoid dimensions and orientations were chosen to reflect the continuity revealed by geostatistical studies and optimized using quantitative kriging neighbourhood analysis. The mineral resource was classified according to CIM Definition Standards on Mineral Resources and Mineral Reserves (CIM 2010).

Key words: Canadian Institute of Mining; Metallurgy and Petroleum (CIM) Definition Standards; EDA (exploratory data analysis); domaining; block model; ordinary kriging; kriging neighbourhood analysis