This subgroup was set up by Dr. Bean (UCD) and is now led by Prof. Seriani (OGS) and Prof. Holliger (ETH). At the kick-off meeting, the invited representatives of the oil industry identified a specific problem as a key inhibitor for progress in interpreting seismic observations in marine environment: in most parts of the world, the sea floor is characterized by a thin (up to several meter thick) layer of unconsolidated "mushy" material that seismically behaves in a way that is not at all understood. Nevertheless, whatever is measured at the surface (reflections from the crustal layers) is affected by it. The subgroup held a meeting at Schlumberger Cambridge Research, Cambridge, UK, in January 2005. The meeting was hosted by Johan Robertsson and Ed Kragh from Schlumberger and chaired by Dr. Bean (UCD). The rationale for the meeting was to explore the current problems, approaches and developments in the "Mushy Sea floor" area and to look to new solutions. Projects were defined that will focus on mushy seafloor parameter estimation (ETH, OGS and Schlumberger), processing of data examples, and a physical modelling approach (UoH, OGS).
This task group is led by Prof. Dahm (UoH) and Prof. Aldo Zollo (Naples). Computational simulations will play an important role in understanding the complex seismic wave fields that are routinely observed at active volcanoes. Clearly, the overall goal here is to develop diagnostic tools to improve the prediction of future eruptions. We note that the Mount Vesuvius - permanently observed by one of our partners (UoN) - is one of the most threatening Geo-hazards in Europe with several million people living in the area that might be affected by an eruption. The subsurface structure of volcanoes is such that special numerical techniques need to be employed that are capable of coping with extremely strong heterogeneities and fluid-filled porous media. A task group meeting was held during the EGU 2005 Meeting in Vienna.