Application of reflectance spectroscopy (400-2500nm) as a new tool in study of environmental mineralogy(case study: Southwestern Australia)

Acid and saline seeps are an increasing problem in most parts of the World and Australia as well. They are areas of bare soil or reduced crop production. Recent laboratory, field, and remote sensing studies have explored the use of visible to short – wave infrared (VIS- SWIR; 400-2500 nm) reflectance data for characterizing the mineralogy of mine wastes, surface mineralogy of acid-saline affected areas and for evaluating waste impacts on hydrologic and biologic systems. Seasonal surface sampling through topo-sequence of the study area and analytical results of XRD, SEM and VNIR indicate that morphological and mineralogical changes within a natural acid saline seep affected landscape revealed that seasonal differences in surface mineralogy. The visible near infra-red (VNIR) reflectance spectra of the surface minerals from unaffected, salt crusted and acid seep areas, showed spectral differences expressed in the VNIR region due to absorption bands of iron oxides and hydroxides. This difference in the surface mineralogy during summer can be readily identified via multi-spectral and hyper-spectral remote sensing methods, and therefore regional mapping com be done for identification of surface mineralogy due to spatial and temporal distribution of acid seeps, which has caused degradation of agricultural lands is suggested.