The Qaleh-Zari Mine is located in the central part of east Iran. It started to produce copper concentrate of 18, 000 tons/year in 1975. The geology of the mine area is composed of Jurassic shale and sandstone, and later volcanic rocks. There is a N-S trending anticline plunging into south. Eruptions of andesite, basalt and lapilli tuff are observed along the anticline. This area is seemed as the center of the mineralization. Copperquartz veins were formed in some fissures which might have been caused by compressional force at two periods.
The direction of flows of ore-forming solution in each vein may suggest ore shoots. Four patterns of the vein system can be seen as follows.
1) No. 1 vein, No. 2 vein (southeast direction) and No. 3 vein make a kind of multiple cymoid loops.
2) Gashes en echelon in the small vein.
3) Echelon vein pattern in the No. 2 vein.
4) Ore-forming solution was enriched in the fissures of which the strike and dip was slightly changed. These features may suggest important keys to promote exploration works of this mine effectively.

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The Iwami zinc-lead-copper deposits are kuroko-type deposits in the "green tuff region" of the Southwest Japan. The ore deposits are divided into three ore zones: the stratiform kuroko ore zone at the top, the massive gypsum ore zone, and the stockwork ore zone extending downwards. Sulfide minerals in the stratiform and stockwork ore zones are sphalerite, pyrite, galena, and chalcopyrite, with minor luzonite and tetrahedrite.
The wall rocks of the stockwork ores consist of dacitic pyroclastics and small rhyolitic intrusives. They are intensively silicified in the high grade ore bodies, and are argillized in the low grade ore bodies. Hydrothermal alteration minerals in the wall rocks are quartz, Mg-chlorite (IIb), interstratified Mg-chlorite-saponite, sericite (1M), and interstratified sericite-montmorillonite (rich in sericite layer), sometimes with minor gypsum. Late calcite occurs in fissures and vugs.
The stratiform kuroko ores consist of the sulfide minerals with minor quartz and Mg-chlorite and rare sericite. Barite occurs in the upper part of the stratiform ore zone, and kaolinite is found sparsely in the lower part. Clay veins and a clay zone surrounding the gypsum ore body consist of sericite and interstratified sericite-montmorillonite with Mg-chlorite, interstratified Mg-chlorite-saponite, quartz and gypsum. Montmorillonite is found in the clay zone at the peripheral part of the stockwork ore zone.
The mineral assemblages and the data of fluid inclusions suggest that the alteration and mineralization in the Iwami ore deposits were brought by the hydrothermal solutions with ionic strength: 0.5 (18, 000 ppm C1), fO₂: 10^-35 atm, fs₂: 10^-12 atm, fCO₂: 0.1-1 atm, and pH: 5.7 at 250°C.

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Recent efforts to use the chlorine content in rocks and minerals as a tool for exploration of base metal deposits, on the basis of chloride-complex model for magmatic hydrothermal ore deposits, seem to have resulted in discouraging conclusion on biotite and bulk samples. Yet we obtained extremely high chlorine values on unaltered granitoids from the lead-zinc mine area at Taishu, and some anomalies in other copper mine areas. In these examples, the chlorine anomalies are found to be largely due to fluid inclusions of high salinity. It appears that the chlorine content in bulk rock analysis can be useful in base metal exploration, if rock types (e.g., magnetite-bearing series or magnetite-free series) and degree and kind of alteration are examined carefully in advance. From the chlorine data together with some geological evidence, a possible area for future exploration of base metal deposits, perhaps of porphyry type, is proposed in the eastern part of the Chugoku batholith. Tin and greisen-type wolframite deposits occur in granitoids belts that have high F/C1 ratios. Fluorine contents of unaltered granitoids spatially related to the ore deposits have some connection with intensity of these mineralizations. It is recommended, however, to use both fluorine and tin in exploration of these types of ore deposits.

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The fluid inclusion study of the Mamut porphyry copper deposit, Sabah, Malaysia was carried out as part of studies of the ore-forming fluids and mineralization of porphyry copper deposits from the Southwestern Pacific island arcs. Polyphase fluid inclusions which contain halite, sylvite, hematite, anisotropic unidentified minerals, and opaque minerals, are observed abundantly in the vein quartz. Gaseous inclusions are also abundant, but liquid inclusions are few. It is inferred from the disappearance temperature of halite that the salinity of fluid would have been in a range between 35 to 55 wt.% NaC1 equivalent concentration. The homogenization temperature of polyphase inclusion ranges from 300°to 480°C, whereas that of liquid inclusion is between 280°C and 325°C. The "boiling" of the fluid is manifested by an intimate coexistence of gaseous and polyphase inclusions, in some samples. The numeral ratio of polyphase inclusion to the total number of inclusion becomes higher in the ore-shell or biotite zone, and at lower levels of the orebody. A low value of the ratio from the core of the orebody is attributable to the abundance of gaseous inclusions. An intimate relation between the abundance of chalcopyrite in sulfide minerals and polyphase inclusions suggests an important role of highly saline fluids in the copper mineralization. It is concluded that the ore-forming fluids at the Mamut porphyry copper deposit were rich in nonvolatile materials including chlorides and that the pressure of the fluids was low enough to emanate the vapor phase. Such characterisitics of fluids at the Mamut deposit are similar to those of the porphyry copper deposits in the southwestern United States.

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[in Japanese]

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