CHARACTERISTIC STUDY OF MAGMA CONTROLLING MINERALIZATION BASED ON GEOCHEMICAL DATA ON WANAGON GOLD DEPOSIT, ERTSBERG DISTRICT, MIMIKA, PAPUA

• Main Author: Kristian Hutagalung, Oscar
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/72565
• Institution: Institut Teknologi Bandung

The need for energy and mineral resources in Indonesia will continue to increase along with the increase in population. To ensure that these needs continue to be met, it is necessary to carry out continuous exploration activities so that energy and mineral resources in Indonesia can be fully used for public welfare. One of the Cu-Au mining activities in Indonesia can be found in Papua, especially in the Ertsber-Grasberg District. Magmatic and tectonic activities followed by hydrothermal events are able to produce Cu and Au mineralization events. One of the deposits, which is the Wanagon Gold Deposit, is closely related to the intrusions that can be found there, such as the Wanagon Sill and Wanagon Dyke. This study aims to understand characteristic and magma fertility from the intrusion complex which could be found on the Wanagon Gold Deposit based on geochemical data so that it can be used for regional vectoring of mineralization surveys related to the skarn-porphyry system. The method used is the analysis of geochemical data from XRD, ICP-MS and electron microprobe analysis using various elemental variation diagrams. The results of data processing show that the intrusions in the study area have alkaline and calc-alkali magma series. The increasing trend of MgO and the decreasing trend of K2O are interpreted to be due to the interaction between the intrusion and the magnesium-rich country rock, forming alteration mineral rich in potassium. The value of Sr/Y against Y indicates the trend of plagioclase mineral formation. Various diagrams of magma fertility show that the intrusion complex in the study area is fertile and productive. The intrusion complex is hydrous and has a high oxygen fugacity value up to FMQ +2, indicating that the magma was formed under high oxidizing conditions.