Interseismic coupling, stress evolution, and earthquake slip on the Sunda megathrust

[1] The extent to which interseismic coupling controls the slip distribution of large megathrust earthquakes is unclear, with some authors proposing that it is the primary control and others suggesting that stress changes from previous earthquakes are of first-order importance. Here, we develop a detailed stress history of the Sunda megathrust, modified by coupling, and compare the correlation between slip and stress with that of slip versus coupling. We find that the slip distributions of recent earthquakes are more consistent with the stress field than with the coupling distributions but observe that in places, the stress pattern is strongly dependent on poorly constrained values of slip in historical earthquakes. We also find that of the 13 earthquakes in our study for which we have hypocentral locations, only two appear to have nucleated in areas of negative stress, and these locations correspond to large uncertainties in the slip distribution of pre-instrumental events. Citation: Nalbant, S., J. McCloskey, S. Steacy, M. NicBhloscaidh, and S. Murphy (2013), Interseismic coupling, stress evolution, and earthquake slip on the Sunda megathrust, Geophys. Res. Lett., 40, 4204–4208,

[1]  D. Wells,et al.  New empirical relationships among magnitude, rupture length, rupture width, rupture area, and surface displacement , 1994, Bulletin of the Seismological Society of America.

[2]  John McCloskey,et al.  Limited overlap between the seismic gap and coseismic slip of the great 2010 Chile earthquake , 2011 .

[3]  Yehuda Bock,et al.  Plate-boundary deformation associated with the great Sumatra–Andaman earthquake , 2006, Nature.

[4]  W. Mccann,et al.  Seismic history and seismotectonics of the Sunda Arc , 1987 .

[5]  K. Sieh,et al.  Rupture Kinematics of the 2005 Mw 8.6 Nias-Simeulue Earthquake from the Joint Inversion of Seismic and Geodetic Data , 2007 .

[6]  M. Ellis,et al.  Topography and tectonics of the central New Madrid seismic zone: Results of numerical experiments using a three‐dimensional boundary element program , 1994 .

[7]  Yehuda Bock,et al.  Crustal motion in Indonesia from Global Positioning System measurements , 2003 .

[8]  Vasily Titov,et al.  Differences in tsunami generation between the December 26, 2004 and March 28, 2005 Sumatra earthquakes , 2006 .

[9]  Shamita Das,et al.  Aftershock zones of large shallow earthquakes: fault dimensions, aftershock area expansion and scaling relations , 2001 .

[10]  Hai Cheng,et al.  Source parameters of the great Sumatran megathrust earthquakes of 1797 and 1833 inferred from coral microatolls , 2006 .

[11]  Jean-Philippe Avouac,et al.  Heterogeneous coupling on the Sumatra megathrust constrained from geodetic and paleogeodetic measurements , 2008 .

[12]  V. E. Levin,et al.  Interseismic coupling and asperity distribution along the Kamchatka subduction zone , 2005 .

[13]  M. Moreno,et al.  2010 Maule earthquake slip correlates with pre-seismic locking of Andean subduction zone , 2010, Nature.