Comparison between Reflectance/Emittance Spectra of Iron-containing Minerals

Correct estimation of the distribution of the iron oxides in open pit mines and the neighbouring regions is a key issue for the ecological state assessment of land cover. For this study airborne (satellite and aircraft) data combined with in-situ and laboratory acquired data were used for assessment of the environmental state from previous mining activities. As main indicator for presence of pollution the iron content was chosen since it could be reliably identified in the ranges used in this study and because of the wide-spread iron in the most of the rock types and soils. The number of samples from every source was taken in the way to be statistically confident. Soil samples together with GPS measurements were collected during a field campaign in the study area for two types of laboratory measurements -chemical and mineralogical analysis and non-destructive spectroscopy. Spectroscopy measurements (laboratory, in-situ and satellite) in visible and near infrared (VNIR) and thermal (TIR) ranges were performed using follows spectrometric systems: ISOH, 0.4-0.8 micrometers; SRM, 0.4-0.82 micrometers; TIRES, 8-16 micrometers; ASTER, 0.4-16 micrometers. Spectral transformations such as normalized difference and relation using two wavelengths were applied for the proper comparison between the data obtained from different sources. Dependence between various spectral transformations and the quantitative content of the iron was established. The achieved results proved that this methodology could be extended for other regions of the country polluted by mining activities mostly by cooper or lead plants.