This article presents a literature review of studies utilising reflectance spectroscopy in geological research. We describe a variety of available spectral libraries together with providing examples of spectral reflectance diagrams, and explain the basic spectral ranges. Geologists can use different methods of data collection, for example, sensors mounted on satellites, airborne [including unmanned aerial vehicle (UAV) platforms] or portable spectroradiometers, and different ways of data processing. Most geological mapping based on reflectance spectroscopy is performed in the Arctic region, where vegetation does not obscure images. However, mineral mapping, studies of hot spring deposits, and rock/soil weathering alterations are also performed in lower latitudes. The development, combination and unification of all spectral data acquisition methods open up new possibilities for applications in a variety of geological and soil studies.

The contemporary retreat of glaciers results in the development of glacial forelands which constitute excellent areas for studies on the initial stages of weathering. This research concentrates on weathering rinds developed on glacially abraded Dachstein limestone surfaces (Eastern Alps) liberated from glacial ice since LIA (mid-19th century). We performed measurements of rock surface micro-roughness and strength (Schmidt hammer), spectral reflectance, and petrographic and microbiological analyses in SEM. There was a time-dependent increase in micro-roughness, decrease in rock strength and decrease in spectral reflectivity, but only within visual light. Rock surfaces on older sites reflected infrared radiation significantly better than younger ones. SEM analysis revealed that angular micro-structures inherited from glacial abrasion dominated in younger sites, eventually giving way to more rounded micro-structures. The structure of rock (micrite versus spar, phlogopite veinlets, etc.) plays a significant role. On older sites, microorganisms were detected within the studied weathering rinds, which probably results in better infrared reflectivity. We advocate the potential role of microorganisms (mainly heterotrophic) in the dissolution of limestone, and the role of cyanobacteria in the formation of the secondary porous limestone layer (extracellular biomineralization).