VERGNOLLE , M.

We use GPS measurements and models of postseismic deformation caused by seven M6.8 to 8.4 earthquakes that occurred in the past 100 years in Mongolia to assess the viscosity of the lower crust and upper mantle. We find an upper mantle viscosity between 1 Â 10 18 and 4 Â 10 18 Pa s. The presence of such a weak mantle is consistent with results...

International audience

International audience

Mogod earthquake (sequence). Each of the larger (M ! 8) earthquakes involved strike-slip faulting averaging more than 5 m and rupture lengths of several hundred kilometers. Available geologic data indicate that recurrence intervals on the major source faults are several thousands of years and distances of about 400 km separate the respective...

An increasing number of observations supports temporal clustering behaviour of earthquakes within fault systems. As earthquake occurrence is mainly controlled by the crustal stresses, it is crucial to determine their spatio-temporal evolution to understand the generation of catastrophic seismic sequences. A possible way to constrain these...

Whereas the spatial and temporal evolution of early postseismic slip (i.e., the first few hours) has been shown to be complex, we do not know well the mechanisms that control its behaviour. One pending question is to know whether or not the rate-and-state friction law is required to explain it, or if the rate-dependent friction law,...

Global positioning system (GPS) time series in Guerrero (Mexico) reveal the existence of large slow slip events (SSEs) at the boundary between the Cocos and North American plates. In this study, we examined the last three SSEs that occurred in 2001/2002, 2006 and 2009/2010, and their impact on the strain accumulation along the Guerrero...

The initiation and the initial evolution of a strike-slip fault are modeled within an elastoplasticity constitutive framework taking into account the evolution of the hardening modulus with inelastic straining. The initial and boundary conditions are similar to those of the Riedel shear experiment. The models first deform purely elastically....

International audience

When analyzing the rupture of a large earthquake, geodetic data are often critical. Yet, these data are generally characterized by either a good temporal (continuous GNSS) or a good spatial (InSAR and subpixel image correlation) resolution, but rarely both. As a consequence, many studies analyze the co-seismic rupture with data also including...

Baikal area show that: (1) the Baikal rift zone is currently opening at 4-5 mm yr −1 in a NW-SE direction and (2) the western part of the Amurian-north China block is moving eastward relative to Eurasia at 5-7 mm yr −1. These results are consistent with recent geodetic studies in Asia, and indicate that crustal motions in Mongolia and north...

Slow slip events (SSEs) in subduction zones have been observed in the last decade with continuous GPS stations. Some of them could be related to the lateral segmentation of subduction interface that seems to be a critical parameter for the propagation of large subduction earthquakes. In 2006, one of the largest SSEs recorded so far was captured...

Slow slip events (SSEs) in subduction zones have been observed in the last decade with continuous GPS stations. Some of them could be related to the lateral segmentation of subduction interface that seems to be a critical parameter for the propagation of large subduction earthquakes. In 2006, one of the largest SSEs recorded so far was captured...

The Guerrero 2006 Slow Slip Event (SSE), Mexico, one of the world's largest observed SSEs, was recorded at 15 continuous GPS stations. This event provides the opportunity to analyse in detail the spatial and temporal evolution of slip at depth, and to constrain the characteristics of a large SSE. We perform an inversion in two steps. First, we...

We present new geodetic results of crustal velocities over a large part of northern Asia based on GPS measurements in the Baikal rift zone and Mongolia spanning the 1994-2002 period. We combine our results with the GPS velocity field for China of Wang et al. [2001] and derive a consistent velocity field for most of Asia. We find contrasted...

It has previously been suggested that ionospheric perturbations triggered by large dip-slip earthquakes might offer additional source parameter information compared to the information gathered from land observations. Based on 3D modeling of GPS- and GLONASS-derived total electron content signals recorded during the 2011 Van earthquake (thrust,...

Doklady Earth Sciences, v. 393, n. 8, p. 1082-1085 [613], 2003

The world's largest observed Slow Slip Events (SSE) occurred in 2001-2002 and 2006 in the Guerrero subduction zone, Mexico. Using an improved GPS processing that accounts for time-varying atmospheric phenomena as well as oceanic, atmospheric and hydrologic loading corrections, the 11 year GPS position time series in Guerrero show a noise...

Many studies of postseismic deformation following large earthquakes focus on time scales ranging from weeks to years following the main earthquake. By contrast, fewer studies have investigated the spatio-temporal distribution of postseismic deformation in the hours to days following the mainshock. Focusing on this early postseismic period is...