|Measurement method(s):||GPS - campaign|
|Duration of observation:||1993 to 2002, 2008 to 2013|
|Inferred cause of deformation:||Magmatic, Surface deposits, Faulting/tectonics|
|Characteristics of deformation:|
GPS campaign data between 1993 and 2002 show that deformation is driven by WNW–ESE tectonic extension at a rate slower than 5 mm yr−1 (Trota et al., 2006). GPS time series between 2008 and 2013 also show evidence for tectonic extension (Okada et al., 2014).
During a period of volcanic unrest at Água de Pau between 2011 and 2012, two further sources of deformation were identified: 1) Permanent edifice-scale inflation centered at NE summit of Fogo, and 2) minor-scale inflation-deflation reversals between Congro, a trachyte maar east of Água de Pau and Furnas volcanoes (Okada et al., 2014).
|Reference:||Trota, A., Houlié, N., Briole, P., Gaspar, J. L., Sigmundsson, F., & Feigl, K. L. (2006). Deformation studies at Furnas and Sete Cidades Volcanoes (São Miguel Island, Azores). Velocities and further investigations. Geophysical Journal International, 166(2), 952-956.|
|Reference:||Okada, J., Sigmundsson, F., Ofeigsson, B., Ferreira, T., Gaspar, J., Lorenzo, M., ... & Rodriques, R. (2014). Volcanic Unrest of Fogo Volcano in 2011-2012, S. Miguel Island, Azores, Observed by Continuous and Campaign GPS Analysis. In EGU General Assembly Conference Abstracts (Vol. 16, p. 13370).|
|Reference:||Smithsonian Institution Global Volcanism Program |