| Title | Zoning of Hydrothermal Alteration in the Western Part of the Hishikari Epithermal Gold Deposit, Southern Kyushu, Japan |
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| Authors | S. Yasuhara, K. Watanabe & E. Izawa |
| Year | 2003 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | |
| Abstract | This study aims to clarify the alteration zoning in the Hishikari deposit from the view of temperature at which host rocks reacted with hydrothermal solutions. The study of the western area of the Hishikari deposit is based on mineral determination by X-ray diffi-action of 203 samples obtained from drill holes. Powdered bulk rock and oriented clay samples were examined to identify clay minerals. We distinguished three types of chloritehmectite mixed-layer minerals by the degree of the shift of basal reflections by ethylene glycol treatment. The clay mineral zoning indicates that favorable conditions for gold mineralization extend west of the present Hishikari deposit. |