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Memorias de investigación
Communications at congresses:
Morfotectonic and seismotectonic evidences of a large seismic source near San Salvador: The Guaycume Fault
Year:2016
Research Areas
  • Geology,
  • Geophysics,
  • Engineering
Information
Abstract
From the analysis of the geological map, neotectonic field observations and morphotectonic analysis of aerial photography, digital elevation models, and fluvial network geometry, we have identified the existence of an active fault poorly known so far. Such a tectonic feature, referred as Guaycume fault, is located just 15 km north of San Salvador. The Guaycume fault is divided into two segments, a western segment 10 km long composed of several parallel faults that distribute the deformation. The eastern segment, separated from the western one by the Cerro del Ojo del Agua, is characterized by a main fault plane with a sharp fault escarpment of 20 Km in length. The analysis of large offsets affecting the river network leads us to calculate a horizontal accumulated displacement of 1750 ± 50 m, and an average vertical displacement of 80 ± 5 m. Using the ages of geological formations on which the network is developed we calculate an average minimum slip rate of 1.08 ± 0.2 mm/yr. This value is significantly lower than the slip rate obtained from geodetic GNSS data probably due to the high uncertainty of the age of the fluvial network. We have revisited the available information regarding the damage distribution generated by the 1917 seismic crisis. We have re-evaluated the spatial distribution of damage. We conclude that Guaycume fault could be the source responsible for the 8 June 1917 Mw 6.4 earthquake, one of the most destructive in the history of San Salvador. We have developed a simulated seismic scenario considering a seismic rupture of the complete Guaycume fault with a Mw 6.8 earthquake. For an event of Mw 6.8 on Guaycume fault, accelerations exceeding 0.6 g are obtained in the region nearest to the source, and greater than 0.2 g in the northern part of San Salvador.
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: José J. Martínez-Díaz (Universidad Complutense de Madrid)
  • Autor: Marcos Plaza Mulas (Universidad Complutense de Madrid)
  • Autor: Jorge Alonso-Henar (Universidad Complutense de Madrid)
  • Autor: José Antonio Álvarez-Gómez (Universidad Complutense de Madrid)
  • Autor: Maria Belen Benito Oterino (UPM)
  • Autor: Carolina Canora (Universidad Complutense de Madrid)
  • Autor: Juan Miguel Insua-Arévalo (Universidad Complutense de Madrid)
  • Autor: Alejandra Staller Vazquez (UPM)
  • Autor: Pilar Villamor (Geological and Nuclear Science Institute)
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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