Publications des scientifiques de l'IRD

Michaud F., Proust J. N., Dano A., Collot Jean-Yves, Guiyeligou G. D., Salazar M. J. H., Ratzov G., Martillo C., Pouderoux H., Schenini Laure, Lebrun J. F., Loayza G. (2016). Flare-shaped acoustic anomalies in the water column along the Ecuadorian margin : relationship with active tectonics and gas hydrates + [Erratum]. Pure and Applied Geophysics, 173 (10-11), p. 3291-3303 [+ erratum p.1429]. ISSN 0033-4553.

Titre du document
Flare-shaped acoustic anomalies in the water column along the Ecuadorian margin : relationship with active tectonics and gas hydrates + [Erratum]
Année de publication
2016
Type de document
Article référencé dans le Web of Science WOS:000385208500005
Auteurs
Michaud F., Proust J. N., Dano A., Collot Jean-Yves, Guiyeligou G. D., Salazar M. J. H., Ratzov G., Martillo C., Pouderoux H., Schenini Laure, Lebrun J. F., Loayza G.
Source
Pure and Applied Geophysics, 2016, 173 (10-11), p. 3291-3303 [+ erratum p.1429] ISSN 0033-4553
With hull-mounted multibeam echosounder data, we report for the first time along the active Ecuadorian margin, acoustic signatures of water column fluid emissions and seep-related structures on the seafloor. In total 17 flare-shaped acoustic anomalies were detected from the upper slope (1250 m) to the shelf break (140 m). Nearly half of the flare-shaped acoustic anomalies rise 200-500 m above the seafloor. The base of the flares is generally associated with high-reflectivity backscatter patches contrasting with the neighboring seafloor. We interpret these flares as caused by fluid escape in the water column, most likely gases. High-resolution seismic profiles show that most flares occur close to the surface expression of active faults, deformed areas, slope instabilities or diapiric structures. In two areas tectonic deformation disrupts a Bottom Simulating Reflector (BSR), suggesting that buried frozen gas hydrates are destabilized, thus supplying free gas emissions and related flares. This discovery is important as it opens the way to determine the nature and origin of the emitted fluids and their potential link with the hydrocarbon system of the forearc basins along the Ecuadorian margin.
Plan de classement
Géologie et formations superficielles [064]
Description Géographique
EQUATEUR
Localisation
Fonds IRD [F B010068264]
Identifiant IRD
fdi:010068264
Contact