Comparison of point-based spectroscopic measurements and close range hyperspectral imaging for analysis of spoil heap mineral composition

Limited availability and high ore prices require alternative methods and strategies to cover the increasing demand for mineral resources. Recycling spoil material from former mining activities may provide a substantial amount of industrially relevant-mate rial. In this feasibility study, remote sensing methods are evaluated to determine mineral composition in spoil heaps. Spectroscopy is a well-established method in the geosciences, and depends on measuring the reflectance of light within the visible and infrared spectral range to allow the identification and mapping of minerals. The method can be applied with single pixel spectrometers for highest accuracy or using hyperspectral cameras (multi-pixel spectrometers) to map larger areas. Spoil heaps require a novel application of hyperspectral imaging at close range (also termed ground-based or terrestrial), which results in a pixel resolution of centimetres and allows scanning of steep-sided slopes. In this project, cooperation between Uni CIPR (Norway) a nd the Department of Remote Sensing and Cartography at the Martin Luther University Halle-Wittenberg (Germany) provides complementary expertise and spectroscopic facilities. Uni CIPR possesses a hyperspectral camera suitable for close range application an d has pioneered the application of close range hyperspectral imaging. The remote sensing group in Halle owns a single pixel spectrometer appropriate for accurate spectroscopic measurements in laboratory and outdoor conditions, and is one of the leading gr oups in spectral characterisation of materials for geoscience research. The project aim is the analysis of spectral measurements with the emerging close range hyperspectral instrumentation, using laboratory and field-based experiments applied to spoil mat erial. The expected result is the intensification of collaboration between the partner groups, addressing aspects of spectral method development as well as a relevant scientific problem in geoscience research.