Mapping the moisture content of coastal sediments using ASTER data for spectroscopic and mineralogical analyses: a case study in South Korea

Abstract

Mineralogical characteristics of coastal sediments and their spectral characteristics related to moisture content were analysed for South Korea in this study, and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) shortwave infrared (SWIR) remote sensing approaches for moisture content mapping based on conventional SAM module were proposed in this study. The mineral composition included the major minerals of quartz, alkali feldspar, plagioclase and calcite and the accessary minerals of mica and clay. The absorption features of coastal sediments studied occurred at wavelengths of 1.900 μm for clay minerals and water, 2.200 μm for clay minerals and 2.350 μm for micas and calcite. The spectral signature changed with increased moisture content as the absorption feature at 2.200 μm and 2.350 μm faded out. The fading absorption features shifted the resampled laboratory spectra in a spectral vector space and enabled the use of a SAM module for the ASTER SWIR data. The SAM method effectively distinguished not only the absolute moisture content distribution using the reference spectra but also the relative moisture content distribution without the actual reference spectra for coastal sediments. Given that mineral composition and absorption feature behaviours with regard to the moisture content of soil samples are similar to coastal sediments, this method may be applicable for soil moisture mapping.

Spectral Responses of As and Pb Contamination in Tailings of a Hydrothermal Ore Deposit: A Case Study of Samgwang Mine, South Korea

“…To evaluate the performance of the empirical equations derived from the calibration model, we used the coefficient of determination (R 2 ), standard error (SE), and p-value for the constant (b 0 ) and coefficients (b n ). The models were then evaluated with the test set based on the R 2 , RMSE, and slope with a 95% confidence limit [28]. The Statistical Package for the Social Sciences (SPSS) Statistics was used for statistical analysis.…”

“…The spectroscopic test provides valuable information on the spectral responses associated with heavy metal contamination, and thus, the test results give a band combination and spectral signatures useful for remote sensing approaches. The visible-near infrared-shortwave infrared (VNIR-SWIR) spectral ranges (350 to 2500 nm) have been used to study the physicochemical properties of mineral objects and the associated environmental changes [12,[16][17][18][19][20][21][22][23][24][25][26][27][28][29].…”

The effects of changing laboratory illumination zenith angle on spectral feature parameters and mineral classification

“…Every dish was painted with the black paint described above to avoid reflection from these dishes. The samples were poured into the dishes flush with the dish edge at a thickness of approximately 1 cm, which is optically impenetrable (Shin et al, 2015;Small et al, 2009). Reflectance spectra of the seven pure minerals were measured under a zenith angle of 5 • (near vertical).…”