Arenal

Volcano number:345033
Region:Mexico and Central America
Country:Costa Rica
Geodetic measurements?Yes
Deformation observation?Yes
Measurement method(s):InSAR, GPS - continuous, GPS - campaign, Levelling, Tiltmeter
Duration of observation:1970s - date
Inferred cause of deformation:Surface deposits
Characteristics of deformation:

There is evidence from multiple methods that the western flank of Arenal is subsiding steadily at a rate of up to 10 cm/yr. Arenal stopped erupting in 2010 after almost 42 years of lava effusion, mostly on the volcano’s western side. Deformation is centred on these recent deposits. Measurements of subsidence at Arenal have been made for several decades, including dry tilt meter (1986-2000, Mora et al., 2013), Electronic Distance Meter (Avard et al., 2012) campaign GPS (Muller et al., in revision) and InSAR (2005-2010, Ebmeier et al., 2010). Long wavelength near-vertical subsidence (2-5 km diameter) has been attributed to elastic loading, consolidation of erupted material and basement subsidence. Higher rate deformation above elevations of ~800 m has a greater component of westward motion and is thought to be caused by multiple shallow, sliding units.

Reference:Ebmeier, S., Biggs, J., Mather, T., Wadge, G., and Amelung, F., 2010, Steady downslope movement on the western flank of Arenal volcano, Costa Rica, Geochemistry, Geophysics, Geosystems, 11(12). doi: 10.1029/2010GC003263
Reference:Avard, G., Pacheco, J., Martinez, M., van der Laat, R., Menjivar, E., Hernendez, H., Marino, T., Sienz, W., Brenes, J., Aguero, A., Soto, J., & J., M., 2012. Volcanic activity in Costa Rica in 2012, OVSICORI Official Annual Summary
Reference:Mora, M. M., Lesage, P., Albino, F., Soto, G. J., and Alvarado, G. E., 2013, Continuous subsidence associated with the long-lasting eruption of Arenal volcano (Costa Rica) observed by dry-tilt stations, Geological Society of America Special Papers, 498,45-56. doi: 10.1130/2013.2498(03)
Reference:Muller, C., R. del Potro, J. Biggs, J. Gottsman, S. K. Ebmeier, S. Guillaume, P-H. Cattin and R. van der Laat. (in revision), Integrated velocity field from ground and satellite geodetic monitoring: Insights from Arenal volcano, under review in Geophysical Journal International.
Location:-84.703, 10.463

Mean line-of-sight velocity at Arenal Volcano (cm/yr), estimated using persistent scatterer methods from TerraSAR-X images, 2011-2013