Raman Spectroscopic Quantitative Study of NaCl-CaCl2-H2O System at High Temperatures and Pressures
LI Jing1, MAO Shi-de1*, ZHENG Hai-fei2,3
1. School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China 2. Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education, Beijing 100871, China 3. School of Earth and Space Science, Peking University, Beijing 100871, China
Abstract：Raman spectra features of the ternary system NaCl-CaCl2-H2O under high temperatures and high pressures were systematically studied in the present work by using hydrothermal diamond anvil cell (HDAC) and Raman shifts of quartz to determine pressures, and it has been obtained for the quantitative relationship between Raman shifts of the O—H stretching band of water, mass fractions of solutes and pressures was obtained. The mass fractions of salts, where salinity of NaCl equal to that of CaCl2, are 4.0 mass%, 8.0 mass%, and 12.0 mass%, respectively. Experimental results indicate that the standardized Raman frequency shift differences of the O—H stretching vibration (Δν(O—H)) rise with the increasing temperatures when the mass fractions of salts and pressures of the NaCl-CaCl2-H2O system remain constant. Δν(O—H) increases with the increase in mass fractions of salts in the system when the temperatures and pressures are constant. Linear relationship between Δν(O—H) and pressure with similar slopes can be found for the NaCl-CaCl2-H2O system with different salinities. The quantitative relationship between Δν(O—H), temperature (T), pressure (P), and mass fraction of solute (M) is P＝-31.892Δν(O—H)+10.131T+222.816M-3 183.567, where the valid PTM range of the equation is 200 MPa≤P≤1 700 MPa, 273 K≤T≤539 K and M≤12 mass%. The equation can be used as a geobarometer in the studies of fluid inclusions of NaCl-CaCl2-H2O system with equal salinities. The method, as a direct geological detecting technique, has a potential application value.
李 晶1，毛世德1*，郑海飞2,3 . 高温高压下NaCl-CaCl2-H2O体系Raman光谱的定量研究 [J]. 光谱学与光谱分析, 2014, 34(07): 1747-1753.
LI Jing1, MAO Shi-de1*, ZHENG Hai-fei2,3 . Raman Spectroscopic Quantitative Study of NaCl-CaCl2-H2O System at High Temperatures and Pressures. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2014, 34(07): 1747-1753.
[1] MAO Cui, CHEN Yong, ZHOU Yao-qi, et al. Spectroscopy and Spectral Analysis, 2010, 30(12): 3258. [2] Ding J Y, Ni P. Acta Petrologica Sinica, 2007, 9: 1. [3] Samson I M, Walker R T. The Canadian Mineralogist, 2000, 38(1): 35. [4] Zheng H F, Qiao E W, Yang Y P, et al. Geoscience Frontiers, 2011, 2(3): 403. [5] Frezzotti M L, Tecce F, Casagli A. Journal of Geochemical Exploration, 2012, 112: 1. [6] Qiao E W, Duan T Y, Zheng H F. Acta Mineralogica Sinica, 2006, 26(1): 89. [7] Qiao E W, Zheng H F, Xu B. Acta Petrologica Sinica, 2008, 24(9): 1981. [8] Yang Y P, Zheng H F. Applied Spectroscopy, 2009, 63(1): 120. [9] WANG Hui-yuan, ZHENG Hai-fei. Spectroscopy and Spectral Analysis, 2012, 32(3): 669. [10] Schimidt C, Ziemann M A. American Mineralogist, 2000, 85: 1725. [11] Carey D M, Korenowski G M. The Journal of Chemical Physics, 1998, 108: 2669. [12] Fraley P E, Narahari Rao K, Jones L H. Journal of Molecular Spectroscopy, 1969, 29(1): 312. [13] Abe N, Ito M. Journal of Raman Spectroscopy, 1978, 7: 161. [14] Kawamoto T, Ochiai S, Kagi H. The Journal of Chemical Physics, 2004, 120: 5867. [15] Bondarenko G V, Gorbaty Y E, Okhulkov A V, et al. The Journal of Physical Chemistry A, 2006, 110(11): 4042.
