
Deformation studies at Furnas and Sete Cidades Volcanoes (São Miguel Island, Azores). Velocities and further investigations
Author(s) -
Trota A.,
Houlié N.,
Briole P.,
Gaspar J. L.,
Sigmundsson F.,
Feigl K. L.
Publication year - 2006
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.2006.03039.x
Subject(s) - geology , north american plate , geodesy , plate tectonics , volcano , geodetic datum , archipelago , seismology , very long baseline interferometry , geodynamics , reference frame , deformation (meteorology) , induced seismicity , seismotectonics , tectonics , oceanography , frame (networking) , telecommunications , computer science
SUMMARY The Azores archipelago is located near the triple junction between the Nubian (NU), North America (NA), and Eurasia (EU) plates. It is characterized by a relatively strong seismicity and active volcanism. The best estimate of the current plate velocities in the area over geologic timescales comes from the NUVEL1‐NNR model (DeMets et al. ) . At the geodetic timescale, plate motion models (Altamimi et al. , Sella et al. ) including GPS, DORIS, SLR and VLBI data currently do not yet include data from the Azores. In the framework of a research project focused on the seismotectonics and volcanotectonics of São Miguel island, we have analysed GPS data collected there in 1993, 1994, 1997, 2000 and 2002. Our analysis determines both the velocity in the REVEL (Sella et al. ) reference frame of São Miguel and its internal deformation. The comparison of the 2000 and 2002 coordinates indicates that São Miguel accommodates moderate WNW–ESE extension at a rate slower than 5 mm yr −1 .