MICHAUD , François

The proposed ages for the collision of the Carnegie Ridge with the South America trench, offshore Ecuador, range from 1 to 15 Ma. In this time frame, many geological features of Ecuador are commonly linked to the subduction of the Carnegie Ridge. (1) After the ridge collided with the trench at ca. 15 Ma, the subsequent interplate coupling...

The longitudinal profile of a river channel can be described in function of mathematical expressions. The logarithmic fit is the most used method to describe the relative equilibrium of a channel elevation profile. Rivers showing zones of high channel gradient and convex-upward profiles can be evaluated in function of the offset distance with...

The subduction of the Nazca Plate below the South American Plate shows the subduction ofaseismic ridges of different origins and morphologies. One of them is the Carnegie Ridge (400kmwide, 2km high) produced by the relationship between the Galapagos Hotspot and the GalapagosSpreading Center. The ages and the effects of the Carnegie Ridge...

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National audience

National audience

Forearc systems develop largely offshore above subduction zones between the trenchand the volcanic arc. The associated forearc basins are generally parallel to the trenchand involve vertical movements (subsidence vs. uplift), influencing the dynamics of thewedge. The objectof the study is the Guayaquil-Tumbes forearc basin belonging to...

Recent deep marine sedimentation in subduction trenches ischaracterized by the inter-stratification of hemipelagic and turbiditesediments locally interbedded with debris flows, which canresult from continental slope shaking by large earthquakes. Theobjective of this study is to describe the morphologic complexityon the Ecuadorian border of the...

The active margin of Ecuador is characterized by strong tectonic erosion that contributes to the formation of adeep trench filled by a complex suite of sedimentary facies. Gravity flow sedimentation is ubiquitous along themargin and facies range from laterally continuous m-thick mass transport deposits to isolated cm-thick...

La subduction de monts sous-marins est connue pour affectersignificativement les marges actives, en augmentant l'érosion tectonique.Par ailleurs, la participation des monts sous-marins àla nucléation/couplage au niveau des grands séismes de subductionest en plein débat. Des modèles analogiques ont montré lesprincipales caractéristiques de ces...

International audience

La croissance de la chaine côtière en Equateur est largement la conséquence de la subduction dela ride de Carnegie (400 km de long, 2 km d'altitude) débutée voilà au moins c.1,5 Ma. Cette chainea dévié les flux sédimentaires issus des Andes, sous alimentant la fosse et le plan de subduction.L'origine, le calendrier, l'amplitude et la...

International audience

International audience

International audience

The uplift of the coastal cordillera of central Ecuador is a likely consequence of the subduction of the Carnegie Ridge, a 400-km-long and 2-km-high topographic asperity. This study aims at analyzing the impact of the subduction of the Carnegie Ridge on the continental shelf sedimentation during the Quaternary. We interpret high-resolution...

International audience

In subduction zones, questioning the causes for variations in interplate coupling and interplate slip behavior implies deciphering how much deep fluid content and flux influence thermo-mechanical features along the plate interface. A key-question in fluid-rich subduction zones is: how ventilated and insulated hydrothermal systems in basaltic...