Using a Diamond Anvil Cell combined with micro Raman spectroscopy, the quantitative relations among Raman shifts, pressure and temperature were obtained for the vibration of O-H in H2O-NaCl, C-O in CO3^2-, S-O in SO4^...Using a Diamond Anvil Cell combined with micro Raman spectroscopy, the quantitative relations among Raman shifts, pressure and temperature were obtained for the vibration of O-H in H2O-NaCl, C-O in CO3^2-, S-O in SO4^2- and C-H in n-heptane-cyclohexane. Based on the quantitative relationships obtained, it is possible to determine the inner pressure for single fluid inclusions and to further determine the isochore of the systems. It is not only helpful to obtain the forming temperatures and pressures of the enclosing minerals, but also to be able to provide information concerning the chemical compositions of the fluid inclusions.展开更多
Up to now,fluid inclusion is still a powerful tool to estimate the temperature and pressure of various geological processes.CO_2-bearing inclusions are commonly found in many environments.Among the CO_2-bearing inclus...Up to now,fluid inclusion is still a powerful tool to estimate the temperature and pressure of various geological processes.CO_2-bearing inclusions are commonly found in many environments.Among the CO_2-bearing inclusions,the most typical are the ternary CO_2-H_20-NaCl inclusions.These saltbearing CO_2 V-L inclusions at room temperatures are coexisting H_2O liquid +CO_2 liquid +CO_2 vapor or coexisting H_20 liquid +CO_2 liquid(or vapor).On heating they often finally homogenize to liquid phase by the bubble disappearance,and they may form CO_2 hydrate and ice during cooling.This paper reports the application of thermodynamic models,including equations of state,to ternary CO_2-H_20-NaCl fluid inclusions.Some simple equations for pressure-temperature-salinity relation on the CO_2 hydrate-liquid-vapor(liquid) surface are developed to calculate the NaCl contents(salinities) of inclusions.With these relations and the latest CO_2 solubility and PVTx models,a new iterative approach is presented to calculate the CO_2 contents of CO_2-H_20-NaCl inclusions on the assumption that the bulk molar volume of an inclusion keeps constant at the disappearances of CO_2 hydrate and vapor bubble.A prominent merit of this method is that the compositions,molar volumes and homogenization pressures of CO_2-H_20-NaCl inclusions can be simultaneously obtained without using experimental optical volume fractions of vapor bubbles at the dissociation temperatures of CO_2 hydrates.Meanwhile,the homogenization pressures and isochores of CO_2-H_2O-NaCl fluid inclusions from updated models are briefly discussed.Calculation program code for the ternary CO_2-H_2O-NaCl inclusions with microthermometric measurement and Raman analysis data as input variables can be obtained from the author.展开更多
Primary high-density fluid inclusions were identified in garnet from ultrahigh pressure eclogite in the southern part of the Sulu terrane. They occur isolatedly or in cluster together with relatively low-density two-p...Primary high-density fluid inclusions were identified in garnet from ultrahigh pressure eclogite in the southern part of the Sulu terrane. They occur isolatedly or in cluster together with relatively low-density two-phase inclu-sions. The eutectic temperature of the inclusions is as low as ≤ -52℃. A bubble was nucleated in a liquid inclusion dur-ing the specific stage of cyclic cooling-heating runs, and the liquid-gas homogenization temperature was measured to be ≤-12.5℃. The composition of the inclusions modeled by the system CaCl2-NaCl-H2O, yields the fluid density of 1.27g/cm3 that corresponds to a pressure of ca. 2.4 GPa at thetemperature of peak eclogite-facies metamorphism, close tothe ultrahigh pressure metamorphic conditions. During theexhumation of the eclogite the inclusions reacted with thehost mineral, forming hydrous silicate minerals that resulted in lowering of the fluid density and its transformation to multi-phase inclusions.展开更多
基金supported by Chinese Natural Science Foundation (No.40873047)
文摘Using a Diamond Anvil Cell combined with micro Raman spectroscopy, the quantitative relations among Raman shifts, pressure and temperature were obtained for the vibration of O-H in H2O-NaCl, C-O in CO3^2-, S-O in SO4^2- and C-H in n-heptane-cyclohexane. Based on the quantitative relationships obtained, it is possible to determine the inner pressure for single fluid inclusions and to further determine the isochore of the systems. It is not only helpful to obtain the forming temperatures and pressures of the enclosing minerals, but also to be able to provide information concerning the chemical compositions of the fluid inclusions.
文摘Up to now,fluid inclusion is still a powerful tool to estimate the temperature and pressure of various geological processes.CO_2-bearing inclusions are commonly found in many environments.Among the CO_2-bearing inclusions,the most typical are the ternary CO_2-H_20-NaCl inclusions.These saltbearing CO_2 V-L inclusions at room temperatures are coexisting H_2O liquid +CO_2 liquid +CO_2 vapor or coexisting H_20 liquid +CO_2 liquid(or vapor).On heating they often finally homogenize to liquid phase by the bubble disappearance,and they may form CO_2 hydrate and ice during cooling.This paper reports the application of thermodynamic models,including equations of state,to ternary CO_2-H_20-NaCl fluid inclusions.Some simple equations for pressure-temperature-salinity relation on the CO_2 hydrate-liquid-vapor(liquid) surface are developed to calculate the NaCl contents(salinities) of inclusions.With these relations and the latest CO_2 solubility and PVTx models,a new iterative approach is presented to calculate the CO_2 contents of CO_2-H_20-NaCl inclusions on the assumption that the bulk molar volume of an inclusion keeps constant at the disappearances of CO_2 hydrate and vapor bubble.A prominent merit of this method is that the compositions,molar volumes and homogenization pressures of CO_2-H_20-NaCl inclusions can be simultaneously obtained without using experimental optical volume fractions of vapor bubbles at the dissociation temperatures of CO_2 hydrates.Meanwhile,the homogenization pressures and isochores of CO_2-H_2O-NaCl fluid inclusions from updated models are briefly discussed.Calculation program code for the ternary CO_2-H_2O-NaCl inclusions with microthermometric measurement and Raman analysis data as input variables can be obtained from the author.
文摘Primary high-density fluid inclusions were identified in garnet from ultrahigh pressure eclogite in the southern part of the Sulu terrane. They occur isolatedly or in cluster together with relatively low-density two-phase inclu-sions. The eutectic temperature of the inclusions is as low as ≤ -52℃. A bubble was nucleated in a liquid inclusion dur-ing the specific stage of cyclic cooling-heating runs, and the liquid-gas homogenization temperature was measured to be ≤-12.5℃. The composition of the inclusions modeled by the system CaCl2-NaCl-H2O, yields the fluid density of 1.27g/cm3 that corresponds to a pressure of ca. 2.4 GPa at thetemperature of peak eclogite-facies metamorphism, close tothe ultrahigh pressure metamorphic conditions. During theexhumation of the eclogite the inclusions reacted with thehost mineral, forming hydrous silicate minerals that resulted in lowering of the fluid density and its transformation to multi-phase inclusions.
