Estudio de la composición mineralógica en formas del relieve de baja pendiente mediante imágenes ASTER en la cuenca del Duero (León, España)

Abstract

This study evaluates the use of ASTER (Advanced Spaceborne Thermal Emission Reflection Radiometer) images for mapping purposes associated with mineral compositions and their relative abundances in flat and gently sloping free crop cultiva- ted areas in the Northwestern Duero Basin. Several image band ratios have been applied to the ASTER multispectral set corresponding to the visible and near-infrared (VNIR) and to the short-wave infrared (SWIR) wavelengths. These band ratios enhance the absorption features related to both electronic and vibrational processes corresponding to iron oxides minerals and phyllosilicates minerals respectively. The obtained results show that the northern and westernmost areas with Paleozoic basement, Neogene and Plio-Quaternary sediments, iron oxides minerals are more frequent. On the other hand, in the Easter- nmost area, characterized by the Quaternary Tuerto and Órbigo river terraces, extensive areas show the possible existence of chlorite and Kaolinite because of the presence of the 2,3 μm absorption feature, and montmorillonite and illite with the 2,2 μm absorption feature. This information could be useful for geological, lithological and mineral prospection mapping in almost flat areas, where the lack of outcrops is a problem.