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We launched an array of nine freely floating submarine seismometers near the Galápagos islands, which remained operational for about two years. P and PKP waves from regional and teleseismic earthquakes were observed for a range of magnitudes. The signal-to-noise ratio is strongly influenced by the weather conditions and this determines the lowest magnitudes that can be observed. Waves from deep earthquakes are easier to pick, but the S/N ratio can be enhanced through filtering and the data cover earthquakes from all depths. We measured 580 arrival times for different raypaths. We show that even such a limited number of data gives a significant increase in resolution for the oceanic upper mantle. This is the first time an array of floating seismometers is used in seismic tomography to improve the resolution significantly where otherwise no seismic information is available. We show that the Galápagos Archipelago is underlain by a deep (about 1900 km) 200–300 km wide plume of high temperature, with a heat flux very much larger than predicted from its swell bathymetry. The decrease of the plume temperature anomaly towards the surface indicates that the Earth’s mantle has a subadiabatic temperature gradient.

International audience; Deciphering the migration pattern of the Esmeraldas submarine Canyon (EC) and its history of cut‐and‐fill allows constraining the Pliocene‐Pleistocene tectonic evolution of the Ecuador‐Colombia convergent margin. Swath bathymetry, multichannel seismic reflection, and chronological data show that the EC is a 143‐km‐long, shelf‐incising, river‐connected canyon that started incising slope apron deposits in the Manglares fore‐arc basin ~5.3 Ma ago. The EC inception appears contemporaneous with the subduction of the Carnegie Ridge that is believed to have initiated 5–6 Myr ago and is considered an indirect cause of the EC formation. During its two‐stage left‐lateral migration, the EC upper‐half scoured deep incisions providing evidences for uplift episodes in the Manglares Basin that are correlated with mid‐Pliocene and Pleistocene regional tectonic events. Glacioeustatic variations contributed significantly to shape the EC and its upslope tributaries by increasing the rate of canyon incision during rapid sea level falls. Faults, folds, and diapirs have structurally controlled the location of the EC and of its tributary canyons, including the Ancon Canyon, which served as the main spillway of the Manglares Basin prior to be cut from its source ~170 kyr ago by the growth of a fault‐related anticline. The margin wedge that hosts the EC is highly unstable as it is cut by active faults and shaken by large subduction earthquakes. Several mass transport deposits have dammed the EC, one of them between >~65 and ~37 kyr causing an impoverishment of detrital material in the trench sedimentation and a possible interruption of the paleoseismological record.

International audience; The devastating April 16, 2016, Pedernales, Ecuador, Mw 7.8 earthquake was among a sequence of ruptures that occurred along the seismically segmented North Andean subduction zone. It caused 700 fatalities, and more than 7,000 people were injured. The magnitude and location of it were similar to those of the May 14, 1942, earthquake, relaxing some of the strain accumulation that had built up over more than 74 years. A weak tsunami was detected in four nearby tide gauges. Analysis of the records provides useful information on the earthquake and tsunami. An estimate of 6.5 cm of coseismic subsidence was reported at the Bahía de Caráquez and Manta locations, while no movement was detected at Esmeraldas and La Libertad. The analysis also supports the existence of two major seismic asperities and a weaker one farther south. A tsunami resonance occurred at the Bay of Salinas, the location of La Libertad, even though the bay is very wide. It was fortunate that it was inconsequential, this time, because the incoming wave was substantially dissipated.

Environmental Modelling & Software, pp. online, 2010; International audience; A numerical simulation of the 26th December 2004 Indian Ocean tsunami for the entire coast of Sri Lanka is presented. The simulation approach is based on a fully nonlinear Boussinesq tsunami propagation model and a robust coseismic source. The simulation is first confronted to available measured wave height. The agreement between observations and the predicted wave heights allowed a reasonable validation of the simulation. As a result a synoptic picture of the tsunami impact is provided over the entire coast of Sri Lanka. It is found that amplification due to shoaling applies mainly in the Eastern and Southern coast because, here, the wave is propagating across the sea floor slope, while propagating along the slope for the Western coast. Spots of high waves are due to wave focusing in some coastal areas while local submarine canyons in other areas inhibit the wave amplification.

International audience; A numerical simulation of the 26th December, 2004 Indian Ocean tsunami of the Tamil Nadu coastal zone is presented. The simulation approach is based on a fully nonlinear Boussinesq tsunami propagation model and included an accurate computational domain and a robust coseismic source. The simulation is first confronted to available tide gauge and runup observations. The agreement between observations and the predicted wave heights allowed a reasonable validation of the simulation. As a result, a full picture of the tsunami impact is provided over the entire coastal zone Tamil Nadu. The processes responsible for coastal vulnerability are discussed.

This manual establishes the guidelines for manage the Sea Bird Electronics profiler (CTD SBE 19 PLUS), as well the procedures for the operation this oceanographic instrument and process the collected data in the oceanographic research cruises of the Southeastern Pacific Joint Regional (CPPS). It is a product of the CPPS- Specialized Database Working Group (GTE-BD) of regional cruises, within the framework of the El Niño Southern Oscillation (ENSO) program and with the participation of Chile, Colombia, Ecuador and Peru. Comisión Permanente del Pacífico Sur (CPPS) Published El presente manual establece las pautas a seguir para el manejo del perfilador Sea Bird Electronics (CTD SBE 19 PLUS), así como, normar los procedimientos para la operación del equipo y procesamiento de datos recolectados en los cruceros regionales del Pacífico Sudeste. Constituye un producto del Grupo de Trabajo Especializado de Base de Datos (GTE-BD) de los cruceros regionales perteneciente a la Comisión Permanente del Pacífico Sur (CPPS), en el marco del programa para el Estudio Regional del Fenómeno El Niño (ERFEN), en el cual participaron instituciones de Chile, Colombia, Ecuador y Perú. Current 14.a Sea surface temperature Subsurface temperature Sea surface salinity Subsurface salinity Validated (tested by third parties) Multi-organisational N/A Sea surface salinity Subsurface salinity Sea surface temperature Subsurface temperature CTD profiler

We determined the distribution and abundance of pelagic copepods in the eastern equatorial Pacific between the coast of Ecuador and the Galapagos Islands under oceanographic conditions associated with the weak La Niña event of 2001. In September-October 2001, negative anomalies of sea surface temperature from this event still remained in the eastern equatorial Pacific, mainly between Ecuador and the Galapagos Islands. The event allowed the incursion of the Humboldt Current farther north and of the Equatorial Undercurrent into the study area, favouring a strong Equatorial Front and upwelling processes. There was evidence of mesoscale eddies in the study area and of the presence of the South Equatorial Current going westward at about 1°N. We identified 107 copepod species and analyzed the distribution of the 10 most abundant ones: Oncaea venusta, Subeucalanus pileatus, S. crassus, S. subtenuis, Paraeucalanus attenuatus, Pleuromamma borealis, Scolecithrix danae, Clausocalanus farrani, Temora discaudata and Calanus chilensis. Copepod distribution and abundance exhibited marked latitudinal differences related to the oceanographic conditions; abundance was highest to the southeast of the Galapagos Islands. Oncaea venusta, Pleuromamma borealis, Calanus chilensis, and Subeucalanus subtenuis were the species that best defined the Equatorial Front and the upwelling process., Se determinó la distribución y abundancia de los copépodos epipelágicos en el Pacífico Ecuatorial Oriental, entre la costa de Ecuador e islas Galápagos, durante condiciones oceanográficas asociadas al evento débil de La Niña 2001. Al final de este evento (Septiembre-Octubre 2001), aun se registraban las anomalías de temperatura superficial en el Pacífico Ecuatorial Oriental, en el área de estudio. Este evento favoreció la incursión hacia el norte de la Corriente de Humboldt y la Subcorriente Ecuatorial, como también la intensificación del Frente Ecuatorial. Se evidenció la presencia de remolinos de mesoescala y de la Corriente Surecuatorial hacia el oeste, alrededor de 1ºN. Se identificaron 107 especies de copépodos y se analizó la distribución de las diez especies más abundantes (Oncaea venusta, Subeucalanus pileatus, S. crassus, S. subtenuis, Paraeucalanus. attenuatus, Pleuromamma borealis, Scolecithrix danae, Clausocalanus farrani, Temora discaudata y Calanus chilensis). La distribución y abundancia de estas especies presentó marcadas diferencias latitudinales asociadas a las condiciones oceanográficas, que mostraron las mayores densidades al sureste de las islas Galápagos. Oncaea venusta, Pleuromamma borealis, Calanus chilensis y Subeucalanus subtenuis fueron las especies que mejor definieron el Frente Ecuatorial y los eventos de surgencia.