1. Mercator & Ortelius Research Centre for Eruption Dynamics, Department of Geology and Soil Sciences, Ghent University, Krijgslaan 281/S8, B-9000 Gent, Belgium (e-mail: Matthieu.KervynDeMeerendre@UGent.be)
2. Cartography & Photo-Interpretation Section, Geology and Mineralogy Department, Royal Museum for Central Africa, Leuvensesteenweg 13, B-3080 Tervuren, Belgium
3. Remote Sensing & Photogrammetry, Department of Geography, Ghent University, Krijgslaan 281/S8, B-9000 Gent, Belgium
4. Department of Geology & Geophysics, University of Hawai‘i at Mānoa, 1680 East–West Road, Honolulu, HI 96822, USA