CO₂レーザーを用いた高スペクトル分解能熱赤外リモートセンシング・データの岩石鉱物織別への応用

抄録

MIRACO₂LAS is an airborne CO₂ laser profiling system that measures bidirectional reflectance for 100 separate wavelengths between 9.1 and 11.2, um. The MIRACO₂LAS was deployed over the Mount Fitton area in South Australia to establish the types of minerals that can be mapped, and to understand better the role of high spectral resolution remote sensing at thermal infrared (TIR) wavelengths, independent of the complicating effects of temperature that beset passive, multispectral TIR systems.
The airborne data were processed to ground reflectance and compared with laboratory spectra of samples collected during the associated field campaign. The reduced airborne data showed good correlation with the laboratory spectra. The minerals apparent in the reduced airborne data include: quartz, K-feldspar, plagioclase, amphibole and kaolinite. The diagnostic spectral signatures of these minerals are all narrow and thus theoretically not detectable using broader band passive systems such as TIMS.
Surface temperature and pseudo-emissivity images, derived from TIMS radiance data using a Residual and a Emissivity, showed that the surface temperature was well separated from the emissivity information. Furthermore, the resultant six-point alpha emissivity spectra from different types of geology showed spectral shapes consistent with laboratory measurements of corresponding rock-chip samples.