MINERAL RESOURCE ASSESSMENT OF PORPHYRY COPPER DEPOSITS IN INDONESIA USING THE USGS 3-PART ASSESSMENT

Convention Bandung 2004 (CB2004) The 33^rd Annual Convention & Exhibition 2004

Indonesian Association of Geologist Horizon Hotel, 29-30 Nov, 1 Dec 2004, Bandung

MINERAL RESOURCE ASSESSMENT OF PORPHYRY COPPER DEPOSITS IN INDONESIA USING THE USGS 3-PART ASSESSMENT

METHOD

Bambang Tjahjono Setiabudi

Directorate of Mineral Resources Inventory
E-mail: BTSetiabudi@hotmail.com

ABSTRACT

Mineral Resource Assessment is a field of research and application of quantitative appraisal methods to evaluate potential mineral resources. Principally it describes mineral deposits, measures their grade and tonnage, estimate the occurrence of the undiscovered deposits and estimates mineral resources in the permissive tracts. The main objectives are to outline the principal areas in Indonesia that have potential for selected undiscovered mineral resources and to estimate the probable amounts of those mineral resources to a depth of 1 km below the earth's surface. The assessment is carried out using the USGS 3-Part Quantitative Mineral Resource Assessment Method. The 3-part method consists of firstly, delineating tracts for commodities and porphyry Cu deposit types based on the geology of the ore deposits, secondly, estimating the amount of resources contained in the undiscovered deposits using appropriate ore characteristics and metal contents based on grade and tonnage models and thirdly, estimating number of undiscovered deposits of each type for each delineated area. Overview of porphyry copper resources in Indonesia as the results of mineral assessment includes standardized database for known mineral deposits and occurrences, digital regional-scale maps of tracts permissive for current known deposits as well as undiscovered mineral resources, and estimates of undiscovered mineral resources within permissive tracts for copper (copper-gold).