Observatorio de I+D+i UPM

Memorias de investigación
Communications at congresses:
Present day kinematics of El Salvador Fault Zone
Year:2016
Research Areas
  • Geology,
  • Geophysics,
  • Engineering
Information
Abstract
The El Salvador Fault Zone (ESFZ) (Martínez-Díaz et al., 2004) is the main structure seismically active in El Salvador. This structure plays an important role in the tectonics of the Chortis block, since its motion is directly related to the drift of the Caribbean plate to the east and not with the partitioning of the deformation of the Cocos subduction. The geometry and the degree of activity of the ESFZ have been studied from geodetic (Staller et al., 2016), geological and paleoseismological studies (Canora et al., 2012; 2014b; Alonso-Henar et al., 2014). In this work we use horizontal GPS velocities (Staller et al., 2016), geological and seismological data to investigate the rate and nature of interseismic strain accumulation on major faults along the ESFZ. This allows us to estimate the distribution of interseismic coupling on the subduction zone interface beneath El Salvador and the kinematics of the tectonic block rotations. Our best model estimates a long-term movement of the Salvadoran forearc of 13.5 ± 1 mm/yr ~NO with respect to the Caribbean plate. The kinematics of the ESFZ confirms an increase in east to west velocity within the forearc block, which is coherent with the regional kinematics of the Chortis Block, as extension is greater in the western part of this block, which combined with the pinning of the forearc block in Guatemala (Álvarez-Gómez et al., 2008), favors east to west strike-slip movement in El Salvador. We find that the data are best fit with a model that includes two intermediate blocks between the main Caribbean and forearc blocks. Our results confirm that the degree of coupling at the interface of the subduction zone off the Salvadoran coastline is practically zero, however the faults of the Salvadoran volcanic arc are almost completely locked.
International
Si
Congress
IASPEI Regional Assembly Latin - American and Caribbean Seismological Commision - LACSC.
970
Place
San José, Costa Rica
Reviewers
Si
ISBN/ISSN
CDP08UPM
Start Date
05/06/2017
End Date
09/06/2017
From page
1
To page
2
IASPEI Regional Assembly Latin - American and Caribbean Seismological Commision - LACSC.
Participants
  • Autor: Alejandra Staller Vazquez (UPM)
  • Autor: José Antonio Álvarez-Gómez (Universidad Complutense de Madrid)
  • Autor: José J. Martínez-Díaz (Universidad Complutense de Madrid)
  • Autor: Maria Belen Benito Oterino (UPM)
Research Group, Departaments and Institutes related
  • Creador: Grupo de Investigación: Ingeniería Sísmica: Dinámica de Suelos y Estructuras
  • Departamento: Ingeniería Topográfica y Cartografía
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