title: Mega-earthquakes rupture flat megathrusts.
abstract: The 2004 Sumatra-Andaman and 2011 Tohoku-Oki earthquakes highlighted gaps in our understanding of mega-earthquake rupture processes and the factors controlling their global distribution: A fast convergence rate and young buoyant lithosphere are not required to produce mega-earthquakes. We calculated the curvature along the major subduction zones of the world, showing that mega-earthquakes preferentially rupture flat (low-curvature) interfaces. A simplified analytic model demonstrates that heterogeneity in shear strength increases with curvature. Shear strength on flat megathrusts is more homogeneous, and hence more likely to be exceeded simultaneously over large areas, than on highly curved faults.
authors.affiliation: Department of Earth Sciences, University of Oregon, 1272 University of Oregon, Eugene, OR 97403, USA. qbletery@uoregon.edu.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Bletery
authors.affiliation: Department of Earth Sciences, University of Oregon, 1272 University of Oregon, Eugene, OR 97403, USA.
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Thomas
authors.affiliation: Department of Earth Sciences, University of Oregon, 1272 University of Oregon, Eugene, OR 97403, USA.
authors.forename: Alan W
authors.initials: AW
authors.lastname: Rempel
authors.affiliation: Department of Earth Sciences, University of Oregon, 1272 University of Oregon, Eugene, OR 97403, USA.
authors.forename: Leif
authors.initials: L
authors.lastname: Karlstrom
authors.affiliation: Université Côte d'Azur, CNRS, OCA, IRD, Géoazur, 250 rue Albert Einstein, Sophia Antipolis, 06560 Valbonne, France.
authors.forename: Anthony
authors.initials: A
authors.lastname: Sladen
authors.affiliation: Université Côte d'Azur, CNRS, OCA, IRD, Géoazur, 250 rue Albert Einstein, Sophia Antipolis, 06560 Valbonne, France.
authors.forename: Louis
authors.initials: L
authors.lastname: De Barros