remote sensing Article Integration of Terrestrial and Drone-Borne Hyperspectral and Photogrammetric Sensing Methods for Exploration Mapping and Mining Monitoring Moritz Kirsch 1,* ID , Sandra Lorenz 1, Robert Zimmermann 1 ID , Laura Tusa 1, Robert Möckel 1, Philip Hödl 1, René Booysen 1,2, Mahdi Khodadadzadeh 1 and Richard Gloaguen 1 ID 1 Helmholtz-Zentrum Dresden-Rossendorf, Helmholtz Institute Freiberg for Resource Technology, Chemnitzer Straße 40, 09599 Freiberg, Germany;
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[email protected] (R.Z.);
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[email protected] (R.G.) 2 School of Geoscience, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, Johannesburg 2000, South Africa * Correspondence:
[email protected]; Tel.: +49-351-260-4439 Received: 20 July 2018; Accepted: 24 August 2018; Published: 28 August 2018 Abstract: Mapping lithology and geological structures accurately remains a challenge in difficult terrain or in active mining areas. We demonstrate that the integration of terrestrial and drone-borne multi-sensor remote sensing techniques significantly improves the reliability, safety, and efficiency of geological activities during exploration and mining monitoring. We describe an integrated workflow to produce a geometrically and spectrally accurate combination of a Structure-from-Motion Multi-View Stereo point cloud and hyperspectral data cubes in the visible to near-infrared (VNIR) and short-wave infrared (SWIR), as well as long-wave infrared (LWIR) ranges acquired by terrestrial and drone-borne imaging sensors. Vertical outcrops in a quarry in the Freiberg mining district, Saxony (Germany), featuring sulfide-rich hydrothermal zones in a granitoid host, are used to showcase the versatility of our approach.