Bulletin of the Geological Society of Malaysia, Volume 42, Dec. 1998, pp. 257 – 268
1Jurusan Teknik Geologi, Institut Teknologi Bandung, Jalan Ganesa 10, Bandung 40132, Indonesia
2PT ANEKA TAMBANG, Jalan Letjen T.B. Simatupang/Lingkar Selatan, Tanjung Barat, Jakarta 12530, Indonesia
3Jurusan Teknik Geologi, Universitas Pembangunan Nasional (UPN), Condong Catur, Yogyakarta, Indonesia
Abstract: The majority of gold-copper mineralization along the Sunda-Banda arc belongs to low-sulfidation epithermal type. Studies by previous authors suggest that mineralization environment changes from low-sulfidation epithermal in the western segment of the arc, minor porphyry and high-sulfidation epithermal to submarine stratiform deposit in the eastern region. It seems that the nature of geologic setting and magmatic evolution exert a profound influence on the mineralization environment.
Most epithermal mineralization are hosted by stratovolcanoes and are associated with old caldera complexes controlled by strike-slip faults and graben subsidence. The present available K-Ar ages of mineralization suggest that the process is related to primarily Late Neogene volcanic eruption of fine silicic pyroclastics of calc-alkaline to potassic calc-alkaline affinity.