Conjugate Fault Deformation Revealed by Aftershocks of the 2013 Mw6.6 Lushan Earthquake and Seismic Anisotropy Tomography

The 2013 Lushan Earthquake in China Tests

Following the devastating 2008 Wenchuan earthquake that ruptured the central–northern segments of the Longmenshan fault in Sichuan, China, many studies assessed its impact on other major faults in this region (e.g., Parsons et al., 2008; Toda et al., 2008). On 20 April 2013, theMw 6.6 Lushan earthquake ruptured the southern segment of the Longmenshan fault, allowing these assessments to be test...

Ductile Gap between the Wenchuan and Lushan Earthquakes Revealed from the Two-dimensional Pg Seismic Tomography

A high-resolution two-dimensional Pg-wave velocity model is obtained for the upper crust around the epicenters of the April 20, 2013 Ms7.0 Lushan earthquake and the May 12, 2008 Ms8.0 Wenchuan earthquake, China. The tomographic inversion uses 47235 Pg arrival times from 6812 aftershocks recorded by 61 stations around the Lushan and Wenchuan earthquakes. Across the front Longmenshan fault near t...

Seismic Fault Rheology and Earthquake Dynamics

As preparation for this Dahlem Workshop on The Dynamics of Fault Zones, specifically on the subtopic “Rheology of Fault Rocks and Their Surroundings,” we addressed critical research issues for understanding the seismic response of fault zones in terms of the constitutive response of fault materials. This requires new concepts and a host of new observations and experiments to document material r...

Seismic anisotropy and large-scale deformation of the Eastern Alps

Renormalization of earthquake aftershocks

Assume that each earthquake can produce a series of aftershock independently of its size according to its “local” Omori’s law with exponent 1+θ. Each aftershock can itself trigger other aftershocks and so on. The global observable Omori’s law is found to have two distinct power law regimes, the first one with exponent p− = 1− θ for time t < t ∗ ∼ κ−1/θ, where 0 < 1−κ < 1 measures the fraction o...