Large-scale inflation of Tungurahua volcano (Ecuador) revealed by Persistent Scatterers SAR interferometry

J. Champenois (1) , V. Pinel (2) , S. Baize (1) , L. Audin (2) , H. Jomard (1) , A. Hooper (3) , A. Alvarado (4) , H. Yepes (2)

1 IRSN - Institut de Radioprotection et de Sûreté Nucléaire
2 ISTerre - Institut des Sciences de la Terre
3 University of Leeds
4 instituto Geofísico

The Tungurahua volcano, in Ecuador, has been experiencing a substantial activity period since 1999, with several eruptions, including those of 2006 and 2008. We use a persistent scatterers approach to analyze a time series of Envisat synthetic aperture radar (SAR) data over the period 2003-2009, to investigate surface deformation in the region of the volcano. We measure a continuous large-scale uplift with a maximum line of sight displacement rate of about 8 mm/yr, which is the first evidence of a sustained inflation in the Andes for an active volcano encompassing several eruptions. We model this signal as magma emplacement in a permanent storage zone at 11.5 km below sea level, with a net inflow rate of 7 million m3/yr. The paroxysmal eruptions in 2006 and 2008 did not seem to disrupt this long-term signal. However, we observe significant deformation during the 2006 eruption consistent with an additional intrusion of 4.5 million m3 of magma. © 2014. American Geophysical Union.

Domaines: Planète et Univers [physics]

J. Champenois, V. Pinel, S. Baize, L. Audin, H. Jomard, et al.. Large-scale inflation of Tungurahua volcano (Ecuador) revealed by Persistent Scatterers SAR interferometry. Geophysical Research Letters, 2014, 41 (16), pp.5821-5828. ⟨10.1002/2014GL060956⟩. ⟨hal-02614039⟩