image: The internal structure of a fault zone evolves during plate subduction. The uneven surface of the incoming plate and off-fault fracturing during subduction generate roughness. Subduction of sediment and wear of geometrical irregularities promote smoothness. Large earthquakes are due to unstable slip of large and smooth patches of the fault. Dean, et al. and Kimura, et al. provide examples of how structural evolution impacts the seismogenic behavior of the fault. This image relates to an article that appeared in the July 9, 2010, issue of Science, published by AAAS. The study, by Dr. S.M. Dean of the University of Southampton in Southampton, UK, and colleagues, is titled, "Contrasting Décollement and Prism Properties over the Sumatra 2004-2005 Earthquake Rupture Boundary." view more
Credit: Image: Science © 2010 AAAS