Advances in Earth Science ›› 2014, Vol. 29 ›› Issue (4): 475-481. doi: 10.11867/j.issn.1001-8166.2014.04.0475

Previous Articles     Next Articles

Advances in Chemical Composition Determination of Individual Fluid Inclusions Trapped within Evaporite Minerals

Ma Lichun 1,Tang Qingfeng 2,Zhang Qi 1,Zhao Yanjun 1,#br# Sun Xiaohong 3,Wang Xin 1,Ren Caixia 1   

  1. 1. MLR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 100037, China;
    2. Beijing Centre for Physical &
    Chemical Analysis, Beijing 100089;
    3. Geological Prospecting Institute of China Chemical Geology and Mine Bureau, Beijing 100013
  • Received:2014-01-28 Online:2014-04-10 Published:2014-04-10

Ma Lichun, Tang Qingfeng, Zhang Qi, Zhao Yanjun, Sun Xiaohong, Wang Xin, Ren Caixia. Advances in Chemical Composition Determination of Individual Fluid Inclusions Trapped within Evaporite Minerals[J]. Advances in Earth Science, 2014, 29(4): 475-481.

Fluid inclusions preserved within evaporite minerals, the reliable recorder of geochemical information of paleo-brines, play an important role in tracing the source of ore-formation material and reconstructing the hydro-geochemical evolution history of paleo-sea/lake. Salt-mine geologists have paid more attention to extractive and determinative techniques. In this paper, the authors summarized recent progresses in the chemical analysis techniques of individual fluid inclusions, including Ultra-micro-chemical Analysis(UMCA),Laser Ablation Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS),Scanning Electron Microscopy with an Attached Energy Dispersive Spectrometer(SEM-EDS)and Laser Raman Microspectroscopy (LRM), and their determinative procedure,application area,analysis accuracy,advances and disadvances. The traditional Ultra-micro-chemical Analysis can be used to determine the concentration of K, Mg, Ca, and SO4, but not the concentration of sodium or chloride in the fluid inclusions. Futhermore, this fluid inclusion extraction requires relatively large inclusions which likely formed during recrystallization.The uncertainty of the UMCA method is typically 10%~17% with 2~3 parallel test. The LA- ICP-MS method is able to analyse small individual inclusions (>10 μm) successfully with a wide range of ions, including major elements, low concentrations of minor and trace irons. The analytical error of this technique is 4%~20%.However the test results can only be reported as ionic ratios because the volume of an inclusion is unknown prior to analysis. The SEM-EDS technique can produce precise measurements of much smaller individual fluid inclusions (>15 μm) with precision of <10%. The detection limits for the SEM-EDS are typically on the order of 0.1 wt% to 1.0 wt%.The ESEM-EDS method is similar to SEM-EDS method, and the major difference is the instrument used for analysis. The precision of ESEM-EDS analysis is between 3% and 6% and the detection limits are 0.1 wt% for all the major irons except Na, which is 0.5 wt%. The Laser Raman Microspectroscopy method is unique nondestructive among all the techniques. It can be used to determine what covalent bonded complexes such as sulfate and bicarbonate. In order to obtain quantitative multi-element analysis data of fluid inclusions, the cross-comparison method of diverse measuring techniques was proposed in the future application.

No related articles found!
Viewed
Full text


Abstract