Open AccessAlteration and Ore Mineralogy Of Metamorphic Rocks Hosted Hydrothermal Gold Deposit At Rumbia Mountains, Bombana Regency, Southeast Sulawesi, Indonesia
Author(s) -
Hasria,
Arifudin Idrus,
I Wayan Warmada
Publication year - 2019
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/375/1/012007
Subject(s) - geology , geochemistry , metamorphic rock , petrography , skarn , placer mining , mineralization (soil science) , quartz , fluid inclusions , mineralogy , paleontology , soil science , soil water
In Indonesia, gold is commonly mined from porphyry, epithermal and skarn type deposits that are commonly found in volcanic/magmatic belts. However, were recently numerous gold prospects discovered in association with metamorphic rocks. This paper is intended to describe an alteration and ore mineralogy hosted by metamorphic rocks at Rumbia mountains, Bombana regency, Southeast Sulawesi province, Indonesia. The study area is found the placer and primary gold hosted by metamorphic rocks. The placer gold is evidently derived from gold-bearing quartz veins hosted by Pompangeo Metamorphic Complex (PMC). This study is conducted in three stages, three stages including desk study, field work and laboratory analysis. Desk study mainly covers literature reviews. Field work includes mapping of surface geology, alteration and ore mineralization as well as sampling of representative rocks types, altered rocks and gold-bearing veins. Laboratory analysis includes the petrologic observation of handspecimen samples, petro graphic analysis of the thin section and ore microscopy for polished section and XRD (X-ray diffraction) analysis. From petrographic observation, the type of alteration found in the study area can be divided into six types including sericitization, argillic, inner propylitic, propylitic, carbonization and carbonatization alterations. These quartz veins are currently recognized in metamorphic rocks at Rumbia mountains. Mineralogically, gold is closely related to chalcopyrite, pyrite, hematite, cinnabar, stibnite and possibly minor goethite. Based on those characteristics, it obviously indicates that the primary gold deposit present in the study area is of orogenic gold deposits type. The orogenic gold deposit is one of the new targets for exploration in Indonesia.