Quartz fluid inclusion

Marutani and Takenouchi (1978) clarified the variations in homogenization temperature and salinity of inclusion fluids in quartz from stockwork siliceous orebodies at the Kosaka mine (Fig. 1.35 Urabe, 1978). They showed that the temperature decreases stratigraphically upwards from stockwork ore zone (280-320°C) to bedded ore zone (260-310°C). Pisutha-Arnond and Ohmoto (1983) carried out fluid inclusion studies of the stockwork siliceous ores from five Kuroko deposits (Kosaka, Fukazawa, Furutobe, Shakanai, and Matsumine) and revealed that black ore minerals (sphalerite, galena, barite) and yellow ore minerals (chalcopyrite, quartz) formed at 200-330°C and 330 50°C, respectively, and salinities of the ore fluids remained fairly constant at about 3.5-6 equivalent wt% NaCl. They analyzed fluids extracted from sulfides and quartz Na = 0.60 0.16 (mol/kg H2O), K = 0.08 0.05, Ca = 0.06 0.05, Mg = 0.013 0.008, Cl = 0.82 0.32, C (as CO2) = 0.20 0.15 and less than 6 ppm each for Cu, Pb, Zn and Fe. 

These predictions are generally in agreement with the observations homogenization temperatures of fluid inclusions in quartz from siliceous ore zone and in barite from black ore zone in the Kuroko deposits is relatively high, ranging from 350 to 250°C, and low, ranging from 250 to 150°C, respectively. 

The temperature of the initial hydrothermal solution is assumed to be 250°C from homogenization temperature of fluid inclusions in vein quartz (Shikazono and Nagayama, 1993). 

Occurrence of pyrrhotite, arsenopyrite and high iron content of sphalerite indicate low fs,2 and /02 conditions. Decrepitation temperatures of fluid inclusions in quartz from Sn-Cu-As stage are 403-322°C (Enjoji and Takenouchi, 1976). 

Main ore minerals are few. They are cinnabar, metacinnabar, stibnite and pyrite. Gangue minerals are quartz and calcite. Fluid inclusion decrepitation temperatures... 

Imai, A., Shimazaki, H. and Nishizawa, T. (1998) Hydrogen isotope study of fluid inclusions in vein quartz of the Hishikari gold deposits, Japan. Resource Geology, 48, 159-170. 

Izawa, E., Yoshida, T. and Sakai, T. (1981) Fluid inclusion studies on the gold-silver quartz veins at Kushikino, Kagoshima, Japan. Minig Geol., Spec. Issue, 10, 25-34. 

The fluid inclusion studies of hot spring-type deposits (Takenouchi, 1981) show a wide range of homogenization temperatures in a given quartz crystal which suggests the boiling of ore fluids. These fluid inclusion studies demonstrate that the hot spring-type formed under shallow depth from the surface. 

Oquartz results for the two deposits are very similar regardless of vein types with averages of +15.7 0.6 %o (la, n=11) for Dufferin and +15.2 0.9 %o (la, n=15) for The Ovens. In addition, there is limited spread in the data for each area despite different vein types having been analyzed. Thus, although veins are classified based on structural type and appearance (e.g., laminated vs. non-laminated, saddle vs. limb, stratabound vs. discordant), the S Oquartz values are the same. In addition, fluid inclusions are similar in quartz from the two areas, with low-salinity (i.e., <6-8 wt% NaCb equiv.) aqueous-carbonic (Xco2 = 0.1-0.3) types dominant. 

The Athabasca sedimentary Basin consists of Helikian polycyclic, mature fluvial to marine quartz-rich sandstone deposited in a near-shore shallow shelf environment (Ramaekers 1990) with an estimated filling beginning at about 1700 to 1750 Ma (Armstrong Ramaekers 1985). The estimate maximum thickness of the basin was 5 to 6 km from fluid inclusion studies (Pagel 1975). 

Siebert C, McManus J, Bice A, Poulson R, Berelson WM (2006b) Molybdenum isotope signatures in continental margin sediments. Earth Planet Sci Lett 241 723-733 Sime NG, De la Rocha C, Galy A (2005) Negligible temperature dependence of calcium isotope fractionation in 12 species of planktonic foraminifera. Earth Planet Sci Lett 232 51-66 Simon K (2001) Does 5D from fluid inclusions in quartz reflect the original hydrothermal fluid Chem Geol 177 483 95... 

Zanon V, Frezzotti ML, Peccerillo A (2003) Magmatic feeding system and crustal magma accumulation beneath Vulcano Island (Italy) evidence from fluid inclusions in quartz xenoliths. J Geophys Res, 108, B6, 2298,... 

Blyth A. (2001) Aspo Hard Rock Laboratory, Matrix Fluid Experiment—Fluid Inclusions Investigation of Quartz. International Technical Document 01-06, Swedish Nuclear Fuel and Waste Management Company (SKB), Stockholm, Sweden, 20p. 

PameU J., Carey P. F., and Monson B. (1996) Fluid inclusion constraints on temperatures of petroleum migration from authigenic quartz in bitumen veins. Chem. Geol. 129, 217-226. 

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