Interface locking along the subduction megathrust from <i>b</i>‐value mapping near Nicoya Peninsula, Costa Rica

  • Abhijit Ghosh
    School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta Georgia USA
  • Andrew V. Newman
    School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta Georgia USA
  • Amanda M. Thomas
    School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta Georgia USA
  • Grant T. Farmer
    School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta Georgia USA

書誌事項

公開日
2008-01
権利情報
  • http://onlinelibrary.wiley.com/termsAndConditions#vor
DOI
  • 10.1029/2007gl031617
公開者
American Geophysical Union (AGU)

この論文をさがす

説明

<jats:p>To understand controlling factors for seismogenesis and strain‐accumulation in subduction megathrusts we examine seismicity patterns across Nicoya, Costa Rica, to determine the overall and spatial variability in the earthquake frequency‐magnitude distribution along the interface. The mean reduction in earthquake activity with magnitude, <jats:italic>b</jats:italic>‐value, is higher (1.06) than global subduction zone averages (0.6–0.8), suggesting the interface here is weakly coupled. Strong spatial variations in <jats:italic>b</jats:italic> are anticorrelated (−0.53) with geodetic estimates of interface locking of E. Norabuena et al. (2004). High <jats:italic>b</jats:italic> prevails in two regions, including the subducted Fisher seamount chain. A broad zone of reduced <jats:italic>b</jats:italic> is observed at and offshore the central Nicoya coast; extending towards an imaged locked patch. These results suggest <jats:italic>b</jats:italic>‐value studies may be useful in identifying regions of increased interface locking in subduction zones, which may indicate regions capable of large slip in future large earthquakes.</jats:p>

収録刊行物

被引用文献 (5)*注記

もっと見る

問題の指摘

ページトップへ