Modelling afterslip and aftershocks following the 1992 Landers earthquake. Frictional properties on the San Andreas fault near Parkfield, California, inferred from models of afterslip following the 2004 earthquake. Geodetic displacements and aftershocks following the 2001, M w = 8.4 Peru earthquake: implications for the mechanics of the earthquake cycle along subduction zones. Dynamics of Izmit earthquake postseismic deformation and loading of the Duzce earthquake hypocenter. Postseismic relaxation driven by brittle creep: a possible mechanism to reconcile geodetic measurements and the decay rate of aftershocks, application to the Chi-Chi earthquake, Taiwan. Inverting geodetic time series with a principal component analysis-based inversion method. Internal deformation due to shear and tensile faults in a half-space. Implications of deformation following the 2002 Denali, Alaska, earthquake for postseismic relaxation processes and lithospheric rheology. M., Burgmann, R., Calais, E., Freymueller, J. Quantitative assessment of great earthquakes in Peru. Measuring the onset of locking in the Peru-Chile trench with GPS and acoustic measurements. An integrated crustal velocity field for the Central Andes. Source model of the 2007 M w8.0 Pisco, Peru earthquake-implications for seismogenic behavior of subduction megathrusts. Radiated seismic energy and earthquake source duration variations from teleseismic source time functions for shallow subduction zone thrust earthquakes. Frictional afterslip following the 2005 Nias-Simeulue earthquake, Sumatra. Modeling the rupture process of the 2003 September 25 Tokachi-Oki (Hokkaido) earthquake using 1-Hz GPS data. A slow thrust slip event following the two 1996 Hyuganada earthquakes beneath the Bungo channel, southwest Japan. Hirose, H., Hirahara, K., Kimata, F., Fujii, N. Interplate coupling beneath NE Japan inferred from three-dimensional displacement field. Repeating earthquakes and interplate aseismic slip in the Northeastern Japan subduction zone. Active faulting and heterogeneous deformation across a megathrust segment boundary from GPS data, South Central Chile (36°–39°s). Moreno, M., Klotz, J., Melnick, D., Echtler, H. Heterogeneous coupling of the sumatran megathrust constrained by geodetic and paleogeodetic measurements. Interseismic coupling and asperity distribution along the Kamchatka subduction zone. Full interseismic locking of the Nankai and Japan-West Kurile subduction zones: an analysis of uniform elastic strain accumulation in Japan constrained by permanent GPS. Absence of strain accumulation in the Western Shumagin segment of the Alaska subduction zone. A dislocation model of strain accumulation and release at a subduction zone. Aseismic slip accounts for as much as 50–70% of the slip budget on the seismogenic portion of the megathrust in central Peru, and the return period of earthquakes with M w = 8.0 in the Pisco area is estimated to be 250 years. The rate-strengthening patches contribute to a high proportion of aseismic slip, and determine the extent and frequency of large interplate earthquakes. The seismogenic portion of the megathrust thus appears to be composed of interfingering rate-weakening and rate-strengthening patches. The most prominent patch of afterslip coincides with the subducting Nazca ridge, an area also characterized by low interseismic coupling, which seems to have repeatedly acted as a barrier to seismic rupture propagation in the past. We show that the Pisco earthquake, with moment magnitude M w = 8.0, ruptured two asperities within a patch that had remained locked in the interseismic period, and triggered aseismic frictional afterslip on two adjacent patches. Here we address this issue by focusing on the central Peru megathrust. The size, location and frequency of earthquakes that a megathrust can generate thus depend on where and when aseismic creep is taking place, and what fraction of the long-term slip rate it accounts for. Thus, active faults seem to comprise areas that slip mostly during earthquakes, and areas that mostly slip aseismically. Although slip is almost purely aseismic at depths greater than about 40 km, heterogeneous surface strain 1, 2, 3, 4, 5, 6, 7, 8 suggests that both modes of slip occur at shallower depths, with aseismic slip resulting from steady or transient creep in the interseismic and postseismic periods 9, 10, 11. Slip on a subduction megathrust can be seismic or aseismic, with the two modes of slip complementing each other in time and space to accommodate the long-term plate motions.
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