Character of seismic motion at a location of a gas hydrate-bearing mud volcano on the SW Barents Sea margin

• Published in: Journal of Geophysical Research: Solid Earth
• Main Authors: Franek, Peter, Mienert, Jürgen, Buenz, Stefan, Géli, Louis
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union (AGU) 2014
• Subjects: VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Marin geologi: 466; VDP::Mathematics and natural science: 400::Geosciences: 450::Marine geology: 466; Håkon Mosby mud volcano; seismic activity; harmonic tremors; tidal correlation; earthquakes; mud eruption; Barents Sea; Arctic
• Online Access: https://hdl.handle.net/10037/13278; https://doi.org/10.1002/2014JB010990

An edited version of this paper was published by AGU. Copyright 2014 American Geophysical Union. Franek, P., Mienert, J., Buenz, S. & Géli, L. (2014). Character of seismic motion at a location of a gas hydrate-bearing mud volcano on the SW Barents Sea margin. Journal of Geophysical Research - Solid Earth, 119(8), 6159-6177. https://doi.org/10.1002/2014JB010990. To view the published open abstract, go to https://doi.org/10.1002/2014JB010990 . The Håkon Mosby mud volcano (HMMV) at 1270 m water depth on the SW Barents Sea slope has been intensively studied since its discovery in 1989. A variety of sensors monitored morphological, hydrological, geochemical, and biological parameters in the HMMV area. An ocean bottom seismometer deployment allowed us to register seismic motion for 2 years, from October 2008 to October 2010. The analysis of seismic records documents two types of seismic signals. The first type are harmonic tremors with frequency peaks around 4–5 and 8–10 Hz that occur in swarms. Their origin could be from fluid flow circulation or resonant vibrations of gas bubbles or from delayed movement of fluid‐rich sediments in the conduit or in a deeper pseudo‐mud chamber of the HMMV. Because swarms occur with a periodicity of ~ 6 h, tide‐related effects are suspected to influence the mechanism originating the tremors. The second type of signals are regional earthquakes that were in 15 cases recognized in seismic records. The activity of harmonic tremors was not significantly affected by earthquakes.