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Estimation of the Terceira Island (Azores) main strain rates from GPS data

Earth, Planets and Space volume 55, pages 637–642 (2003)Cite this article

Abstract

The nature and location of the present EUR/AFR boundary configuration in the Azores region is controversial and, in particular, the pattern of the present day deformation associated with plate boundary processes, is still unknown. We present here GPS data from 10 stations, in a segment of this boundary (Terceira Island), where data at 2 epochs (1999 and 2001) are available. GPS data were processed using GAMIT and FONDA, with horizontal position repeatability circa 3 mm and 2 mm, respectively, for 1999 and 2001 epochs. Stations horizontal displacements range from 0.96 to 4.60 mm/yr. Strain analysis indicates compression for four sub-networks. The rates of local rotation are consistent for three sub-networks on the western part of Terceira, exhibiting a clockwise rotation of about 8° per million years. Although they are still preliminary, these results are discussed in relation with the expected behaviour from regional geodynamic constraints and past geodetic studies.

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Authors and Affiliations

  1. Department of Mathematics, Faculty of Sciences, University of Lisbon, Portugal

    Ana Navarro & João Catalão

  2. CGUL, Faculty of Sciences, University of Lisbon, Portugal

    Jorge Miguel Miranda

  3. Delft Institute for Earth-Oriented Space Research, TU Delft, Kluyverweg 1, 2629 HS, Delft, Netherlands

    Rui Manuel Fernandes

  4. Department of Computer Science, University of Beira Interior, Covilhã, Portugal

    Rui Manuel Fernandes

Authors
  1. Ana Navarro
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  2. João Catalão
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  3. Jorge Miguel Miranda
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  4. Rui Manuel Fernandes
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Correspondence to Ana Navarro.

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Navarro, A., Catalão, J., Miranda, J.M. et al. Estimation of the Terceira Island (Azores) main strain rates from GPS data. Earth Planet Sp 55, 637–642 (2003). https://doi.org/10.1186/BF03352470

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  • DOI: https://doi.org/10.1186/BF03352470

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