ZHENG Chao-fei1,2, ZHANG Zheng-wei1, WU Cheng-quan1,2, YAO Jun-hua1,2
(1. State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China;
2. University of the Chinese Academy of Sciences, Beijing 100039, China)
Abstract：Petrographic observation and microthermometric measurement of quartz inclusions from the Pasir Manggu, Cibak and Cipirit ore blocks from Ciemas, Indonesia, allow for the following conclusions to be drawn: inclusions are mainly liquid-rich two phase inclusions, incorporating a NaCl-H2O fluid system, with homogenization temperatures occurring mainly between 240 to 320 ℃ and salinities clustering between 14%―17% NaCl eqv. The fluid densities calculated from former data are 0.85―0.95 g/cm3. The fluid pressure ranges from 4.1 MPa to 46.8 MPa, indicating a relevant ore-forming depth of 150―1730 m and revealing a generally epithermal deposit. According to the geological characteristics and the quartz inclusions, we speculate that the Ciemas gold deposit is a high-sulfidation epithermal deposit. It may belong to a porphyry-(high-sulfidation) epithermal metallogenic system where the mechanism of gold precipitation is the result of a mixing of different ore-forming fluids.
Key words：fluid inclusions; epithermal gold deposit; fluid mixing; Ciemas gold deposit; Indonesia
E-mail: zhangzhengw@hotmail.com
ACTA MINERALOGICA SINICA Vol. 34, No. 4, 2014, Page 581-590
