Rock geochemistry related to mineralization processes in geothermal areas

Global Colloquium on GeoSciences and Engineering 2017

Al Kausar, A.^1 ; Indarto, S.^1 ; Setiawan, I.^1

Research Center of Geotechnology, LIPI, Bandung, Indonesia^1

关键词: Geochemical analysis;    Geothermal areas;    Geothermal systems;    Heat and mass transfer;    Meteoric waters;    Mineralization process;    Papua New Guinea;    Subsurface temperature;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/118/1/012071/pdf
DOI  :  10.1088/1755-1315/118/1/012071

来源: IOP

【 摘 要 】

Abundant geothermal systems in Indonesia suggest high heat and mass transfer associated with recent or paleovolcanic arcs. In the active geothermal system, the upflow of mixed fluid between late stage hydrothermal and meteoric water might contain mass of minerals associated with epithermal mineralisation process as exemplified at Lihir gold mine in Papua New Guinea. In Indonesia, there is a lack of study related to the precious metals occurrence within active geothermal area. Therefore, in this paper, we investigate the possibility of mineralization process in active geothermal area of Guci, Central Java by using geochemical analysis. There are a lot of conducted geochemical analysis of water, soil and gas by mapping the temperature, pH, Hg and CO2distribution, and estimating subsurface temperature based on geothermometry approach. Then we also apply rock geochemistry to find minerals that indicate the presence of mineralization. The result from selected geothermal area shows the presence of pyrite and chalcopyrite minerals on the laharic breccias at Kali Putih, Sudikampir. Mineralization is formed within host rock and the veins are associated with gold polymetallic mineralization.