|Region:||Mexico and Central America|
|Measurement method(s):||InSAR, GPS - campaign|
|Duration of observation:||2007-2010 (InSAR), 2009 (campaign GPS)|
|Inferred cause of deformation:||Hydrothermal|
|Characteristics of deformation:|
No deformation was detected at Santa Ana (detection threshold 6.1 cm/yr) during an ALOS survey of Central American volcanoes (Ebmeier et al., 2013).
Campaign GPS measurements during 2009 showed up to 139 mm inflation between February and July at the Coatepeque Caldera, followed by lower magnitude deflation from July to November (Lechner, 2010). The deformation is attributed to activity in the hydrothermal system beneath the caldera.
|Reference:||Ebmeier, S. K., J. Biggs, T. A. Mather, and F. Amelung (2013), On the lack of InSAR observations of magmatic deformation at Central American volcanoes, J. Geophys. Res. Solid Earth, 118, 2571–2585, doi:10.1002/jgrb.50195.|
|Reference:||Lechner, H. N. (2010), Differential GPS as a monitoring tool on Volcano Santa Ana (Ilamatepec) and the Coatepeque Caldera, El Salvador, MSci. Thesis, Michigan Technological Univeristy. Accessed online at http://www.geo.mtu.edu/rs4hazards/Project%20resources/theses/lechner_thesis.pdf on 22/07/15|
View from the southeast of Santa Ana (right) and Izalco (left) volcanoes. Photo: Lee Siebert, 1999 (Smithsonian Institution).