1. 1U.S. Geological Survey, California Volcano Observatory, Moffett Field, California, U.S.A.
2. 2Department of Geosciences, Warner College of Natural Resources, Colorado State University, Fort Collins, Colorado, U.S.A.
3. 3Department of Geological and Mining Engineering and Sciences, Michigan Technological University, Houghton, Michigan, U.S.A.
4. 4Departamento de Obras Civiles y Geología, Universidad Católica de Temuco, Temuco, Chile
5. 5Millennium Institute on Volcanic Risk Research – Ckelar Volcanoes, Antofagasta, Chile
6. 6U.S. Geological Survey, Alaska Volcano Observatory, Anchorage, Alaska, U.S.A.