Journal of Seismology

, Volume 9, Issue 4, pp 383–404 | Cite as

The seismic velocity structure north of Iceland from joint inversion of local earthquake data

  • C. Riedel
  • A. Tryggvason
  • T. Dahm
  • R. Stefanson
  • R. Bödvarson
  • G. B. Gudmundsson
Article

Abstract

The tectonics of North Iceland is dominated by interaction of the Iceland hot spot and the mid-oceanic Kolbeinsey Ridge. Transform movement along the transition zone, often called Tjörnes Fracture Zone, and the seismicity it generates has been documented in the past. This study uses the seismicity data of the permanent South Iceland Lowland (SIL) network to quantify velocity structure from travel time inversion. The SIL seismic dataset is capable of illuminating parts of the region in a 3D seismic velocity inversion, primarily between 7 and 12 km depth, with less resolution elsewhere because of the sparse setup of the monitoring network. The problem has been analysed in 1, 2 and 3 dimensions and evaluated with 4 different inversion tools. The study reports a correlation of a seismic velocity anomaly in compressional wave velocity vp and shear wave velocity vs with the Husavik-Flatey fault and a further subsurface lineament stretching between the islands of Flatey and Grimsey. Finally, our results support a decrease of crustal thickness between the mainland and the island of Grimsey.

Key Words

Tjörnes Fracture Zone plume-ridge interaction transform zone SIMUL2000 seismic tomography Iceland Grimsey crustal structure 

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Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  • C. Riedel
    • 1
  • A. Tryggvason
    • 2
  • T. Dahm
    • 1
  • R. Stefanson
    • 3
  • R. Bödvarson
    • 2
  • G. B. Gudmundsson
    • 3
  1. 1.Institut für GeophysikHamburgGermany
  2. 2.Institutionen för GeovetenskaperAvdelningen för fasta jordens fysikUppsalaSweden
  3. 3.Icelandic Meteorological OfficeReykjavikIceland

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