AGURTO-DETZEL , Hans

We study source parameters of a cluster of 21 very shallow (<1 km depth) small‐magnitude (Mw < 2) earthquakes induced by percolation of water by gravity in SE Brazil. Using a multiple empirical Green's functions (meGf) approach, we estimate seismic moments, corner frequencies, and static stress drops of these events by inversion of their...

We investigate a long series of small earthquakes (magnitude < 3) with annual cycles between 2004 and 2010 that occurred in the northeastern Paraná Basin, Brazil. These events were attributed to pore pressure increase in a fractured aquifer caused by the drilling of several water wells down to depths of ∼200 m. Because of the poor depth...

Subduction zones generate the largest earthquakes on Earth, yet their detailed structure, and its influence on seismic and aseismic slip, remains poorly understood. Geological studies of fossil subduction zones characterize the seismogenic interface as a 100 m–1 km thick zone 1–3 in which deformation occurs mostly on metres-thick faults 1,3–6 ....

International audience

High-Rate (HR) GPS time series following the 2016 Mw 7.8 Pedernales earthquake suggest significant postseismic deformation occurring in the early postseismic period (i.e. first few hours after the earthquake) that is not resolved with daily GPS time series. To understand the characteristics of early postseismic deformation, and its relationship...

The north Ligurian margin is a complex geological area in many ways. It has witnessed several phases of highly contrasting deformation styles, at both crustal scale and that of shallower cover tectonics, simultaneously or in quick succession, and with significant spatial variability. This complex interplay is mirrored in the resulting intricate...

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...

The Ecuadorian forearc is a complex region of accreted terranes with a history of largemegathrust earthquakes. Most recently, aMw7.8 megathrust earthquake ruptured the plateboundary offshore of Pedernales, Ecuador on 16 April 2016. Following this event, an inter-national collaboration arranged by the Instituto Geofisico at the...

International audience

The Ecuadorian convergent margin has experienced many large mega-thrust earthquakes in the past century, beginning with a 1906 event that propagated along as much as 500 km of the plate interface. Many subsections of the 1906 rupture area have subsequently produced Mw ≥ 7.7 events, culminating in the 16 April 2016, Mw 7.8 Pedernales earthquake....

The Mw7.8 Pedernales earthquake is associated with the subduction of the Nazca Plate beneath the South American Plate. The mainshock caused many casualties and widespread damages across the Manabi province. The 150 km-long coseismic rupture area is found beneath the coastline, near 25 km depth. The rupture propagated southward and involved the...

Since July 2019, The Ayiti-seismes citizen network (ASCN) has been detecting and locating, in real time, earthquakes occurring in Haiti of magnitude ≥ 2.5. ASCN is based on both Seiscomp3 modules and Géoazur in-house software, and uses seismic signals from (1) low-cost, low-maintenance Raspberry Shake (RS) instruments installed in Haiti and (2)...

The north Ligurian margin is a complex geological area in many ways. It has witnessedseveral phases of highly contrasting deformation styles, at both crustal scale and that of shallower covertectonics, simultaneously or in quick succession, and with significant spatial variability. This complexinterplay is mirrored in the resulting intricate...

On April 16th 2016 a Mw 7.8 earthquake ruptured the central coastal segment of the Ecuadorian subduction zone. Shortly after the earthquake, the Instituto Geofisico de la Escuela Politecnica Nacional of Ecuador, together with several international institutions deployed a dense, temporary seismic network to accurately categorize the post-seismic...

Megathrust ruptures and the ensuing postseismic deformation cause stress changes that may induce seismicity on upper plate crustal faults far from the coseismic rupture area. In this study, we analyze seismic swarms that occurred in the north Ecuador area of Esmeraldas, beginning two months after the 2016 Mw7.8 Pedernales, Ecuador megathrust...

Understanding the physical parameters and processes that control the seismogenic behavior of subduction zones megathrust faults remains one of the outstanding challenges in Earth Sciences. Here we present important results from several large seismic experiments aimed at addressing this question. These experiments focused on the three subduction...