Using Laser Raman Microprobe and Fused Silica Capillaries to Determine Salinity of Fluid Inclusions

Abstract

Salinity is one of the most important parameters of fluid inclusions. The salinity of fluid inclusions can be measured quickly and accurately by using a Laser Raman Microprobe. The accuracy of the standard sample plays an important role in this method. The technique of synthesizing fluid inclusions in fused silica capillaries is a new method to prepare standard samples. In this study, this technique was applied to synthesize the fluid inclusions with different concentrations of salinity, which were used to establish the Raman standard curve. The results of microthermometry showed that the accuracy of salinity in synthesized fused silica capillaries was 0.5%. The concentrations of salinity of synthesized fluid inclusions in quartz and halite were determined to verify the standard curve with 1% error between measured value and theoretical value. Compared with the method of synthesizing fluid inclusions in minerals and the method of prepare samples in glass (quartz) tube, this technique can synthesize fluid inclusions quickly and prepare small size samples which are similar to the fluid inclusions in geology samples.

Keywords

• synthesizing inclusions in fused silica capillaries
• laser raman microprobe
• salinity
• microthermometry