VACA , Sandro

The recent development of a national seismic broadband network in Ecuador enables us to determine a comprehensive catalog of earthquake focal mechanisms at the country-scale. Using a waveform inversion technique accounting for the spatially variable seismic velocity structure across the country, we provide location, depth, focal mechanism and...

The northern Ecuador segment of the Nazca/South America subduction zone shows spatially heterogeneous interseismic coupling. Two highly coupled zones (0.4° S–0.35° N and 0.8° N–4.0° N) are separated by a low coupled area, hereafter referred to as the Punta Galera-Mompiche Zone (PGMZ). Large interplate earthquakes repeatedly occurred within the...

International audience

International audience

In the paper entitled "Two independent real-time precursors of the 7.8 M earthquake in Ecuador based on radioactive and geodetic processes – Powerful tools for an early warning system", Toulkeridis et al. (2019) claim that they found radiation and GPS signal anomalies before the April 16th 2016 Pedernales earthquake (Ecuador) and that their...

International audience

International audience

Along the Ecuadorian margin, the North Andean Sliver is moving in the northeastward direction due tothe oblique subduction of the Nazca plate. The opening of the gulf of Guayaquil is a consequence of thismotion. Two principal models compete to explain the opening. One proposes an opening achievedessentially with strike slip motion along a...

International audience

International audience

At subduction zones, transient aseismic slip occurs either as afterslip following a large earthquake or as episodic slow slip events during the interseismic period. Afterslip and slow slip events are usually considered as distinct processes occurring on separate fault areas governed by different frictional properties. Continuous GPS (Global...

The 2019/05/26 Northern Peru earthquake (Mw = 8) is a major intermediate-depth earthquake that occurred close to the eastern edge of the Nazca slab flat area. We analyze its rupture process using high-frequency back-projection and seismo-geodetic broadband inversion. The latter approach shows that the earthquake propagated with almost purely...

International audience

The Ecuadorian subduction regularly hosts large earthquakes. Among them, the Mw 8.8 1906 earthquake is the 7th biggest known event. Following the recent 2016 Mw 7.8 Pedernales earthquake, a large deployment of onshore/offshore seismological stations, in addition to the permanent seismological/geodetical network, revealed a complex slip behavior...

In active subduction zones, the sum of the deformation over many seismic cycles accounts for the long-term cumulated deformation of the forearc. Along the Andean coast, several studies have suggested a correlation between the seismic segmentation of the megathrust and the morpho-tectonic segmentation of the forearc. Large megathrust earthquakes...