Structure and Composition of the Plate-Boundary Slip Zone for the 2011 Tohoku-Oki Earthquake

Frederick M. Chester and Christie Rowe and Kohtaro Ujiie and James Kirkpatrick and Christine Regalla and Francesca Remitti and J. C. Moore and Virginia Toy and Monica Wolfson-Schwehr and Santanu Bose and Jun Kameda and James J. Mori and Emily E. Brodsky and Nobuhisa Eguchi and Sean Toczko and Expedition 343 and 343T Scientists. ( 2013 )
in: Science, 342:6163 (1208-1211)

Abstract

The mechanics of great subduction earthquakes are influenced by the frictional properties, structure, and composition of the plate-boundary fault. We present observations of the structure and composition of the shallow source fault of the 2011 Tohoku-Oki earthquake and tsunami from boreholes drilled by the Integrated Ocean Drilling Program Expedition 343 and 343T. Logging-while-drilling and core-sample observations show a single major plate-boundary fault accommodated the large slip of the Tohoku-Oki earthquake rupture, as well as nearly all the cumulative interplate motion at the drill site. The localization of deformation onto a limited thickness (less than 5 meters) of pelagic clay is the defining characteristic of the shallow earthquake fault, suggesting that the pelagic clay may be a regionally important control on tsunamigenic earthquakes.

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BibTeX Reference

@ARTICLE{Chester06122013,
    author = { Chester, Frederick M. and Rowe, Christie and Ujiie, Kohtaro and Kirkpatrick, James and Regalla, Christine and Remitti, Francesca and Moore, J. C. and Toy, Virginia and Wolfson-Schwehr, Monica and Bose, Santanu and Kameda, Jun and Mori, James J. and Brodsky, Emily E. and Eguchi, Nobuhisa and Toczko, Sean and 343, Expedition and Scientists, 343T },
     title = { Structure and Composition of the Plate-Boundary Slip Zone for the 2011 Tohoku-Oki Earthquake },
   journal = { Science },
    volume = { 342 },
    number = { 6163 },
      year = { 2013 },
     pages = { 1208-1211 },
       url = { http://www.sciencemag.org/content/342/6163/1208.abstract },
       doi = { 10.1126/science.1243719 },
  abstract = { The mechanics of great subduction earthquakes are influenced by the frictional properties, structure, and composition of the plate-boundary fault. We present observations of the structure and composition of the shallow source fault of the 2011 Tohoku-Oki earthquake and tsunami from boreholes drilled by the Integrated Ocean Drilling Program Expedition 343 and 343T. Logging-while-drilling and core-sample observations show a single major plate-boundary fault accommodated the large slip of the Tohoku-Oki earthquake rupture, as well as nearly all the cumulative interplate motion at the drill site. The localization of deformation onto a limited thickness (less than 5 meters) of pelagic clay is the defining characteristic of the shallow earthquake fault, suggesting that the pelagic clay may be a regionally important control on tsunamigenic earthquakes. }
}