Extraction and isotopic analysis of fluid inclusions in halites.

Abstract

Basic techniquefor the extraction and isotopic analysis of fluid inclusions in halite was investigated using synthetic single crystals of halite and three natural halite samples from China.Vacuum ball-mill, vacuum decrepitation and vacuum melting methods were examined for the extraction of fluid inclusions.Results of analyses on SD and 6'x0 of the water in fluid inclusions extracted by the ball-mill method from synthetic single crystals agreed with those of the mother solution from which the single crystals were formed. Although the 8'80 value of the water extracted by the melting method agrees well with that of the mother solution, the bD value was about 7 % more negative than that of the mother solution .There was a great difference in both SD and S'50 of the water extracted by the two methods applied to the identical natural halite samples; the melting method gave consistently more negative values for both SD and b'x0 compared with those by the ball-mill method.

Fluid evolution and ore deposition in the Harz Mountains revisited: isotope and crush-leach analyses of fluid inclusions

“…Variations in δ 2 H w in banded ore minerals cover a range of 40‰. At the temperatures recorded from the fluid inclusions for the mineralizing events, hydrogen isotope values of fluid inclusions are generally assumed to be unaffected by diagenetic alteration (Horita and Matsuo 1986;Ohba and Matsuo 1988;Mavrogenes and Bodnar 1994;Simon 2001;Baatartsogt et al 2007a;Bakker 2009). The large isotope range observed in δ 2 H w is, thus, also indicative of fluids originating from different reservoirs, considering that δ 2 H w modifications of circulating fluids through WRI processes are generally thought to be limited due to the sheer amount of water with respect to hydrogen-bearing reactants (e.g., O'Neil and Kharaka 1976;Yeh and Epstein 1978).…”

2020 LANL Contributions to the BATS Test in WIPP

“…Previous efforts to reliably and reproducibly analyze the isotopic content of NaCl fluid inclusions have employed a variety of methods (Horita and Matsuo, 1986;Knauth and Beeunas, 1986) with all methods having some limitation in their application. We have initially chosen to employ a vacuum crushing technique due to its simplicity of implementation and capability of analysis of small samples.…”

Precise determination of hydrogen and oxygen isotope ratios of water in fluid inclusions of quartz and halite.

“…The H-5 halite is marine in origin and a large amount of Mg 21 (Ca2+) is contained in the brine in fluid in clusions. In such a case some hydrate salts con taining Mg` may form when the vesicles are broken to evaporate during the crushing process (Horita and Matsuo, 1986). Hydrate salts, such as KMgC13.6H2O (carnallite), MgC12.6H2O (bischofite), CaSO4.2H2O (gypsum), CaMg2C16.12H20 (tachhydrite) never release all the oxygen atoms contained in the water of crystallization at the temperature of post-heating of 280°C, e.g., MgC12.6H2O --p MgO + 5H2O + 2140.…”

“…The grain size of the samples prepared for crushing was 6-10 mesh. Halite samples were not pretreated to avoid contamina tion as suggested by Horita and Matsuo (1986). …”

“…Kita (1981) devised a ball mill made of Pyrex glass with an alumina ball. Kazahaya and Matsuo (1985) and Horita and Matsuo (1986) applied this ball mill to extract volatiles from inclusions in quartz and halite, respectively, for isotope analyses.…”