Laboratory technique for quantitative thermal emissivity measurements of geological samples

Journal of Earth system science

Archana Nair1²  George Mathew1²  Kanchan Pande1²  T K Gundu Rao2¹ 

[1] Sophisticated Analytical Instrumentation Centre, Indian Institute of Technology, Bombay, Powai, Mumbai 400 076, India.$$;Department of Earth Sciences, Indian Institute of Technology, Bombay, Powai, Mumbai 400 076, India.$$

关键词: Emissivity;    infrared spectroscopy;    thermal emission;    planetary geology.;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

Thermal infrared spectroscopy is a powerful technique for the compositional analysis of geological materials. The spectral feature in the mid-IR region is diagnostic of the mineralogy and spectral signatures of mixtures of minerals that add linearly, and therefore, can be used as an important tool to determine the mineralogy of rocks in the laboratory and remotely for planetary exploration. The greatest challenge in the emission measurement lies in the measurement of the weak thermal photons emitted from geological materials in a laboratory setup, and accurately records the temperature of the rock sample. The present work pertains to the details of a new Thermal Emission Spectrometer (TES) laboratory that has been developed under the ISRO Planetary Science and Exploration (PLANEX) programme, for emission related mineralogical investigations of planetary surfaces. The focus of the paper is on the acquisition and calibration technique for obtaining emissivity, and the deconvolution procedure to obtain the modal abundances of the thermal emission spectra in the range of 6–25 𝜇 m using Fourier Transform Infrared (FTIR) spectroscopy. The basic technique is adopted from the work of Ruff et al (1997). This laboratory at the Department of Earth Sciences, IIT-Bombay is currently developing pure end mineral library of mineral particulates (> 65 𝜇m), and adding new end members to the existing ASU spectral library. The paper argues the need for considering Lunar Orbiter Thermal Emission Spectrometer (LOTES) for future Indian Moon mission programme (Chandrayan-II) to determine evidences of varied lithologies on the lunar surface.

【 授权许可】

Unknown