Dynamic controls of fluid and gas flow at North Alex Mud Volcano, West Nile Delta

OS51D-01 The North Alex Mud Volcano (NAMV) is located at a water depth of 500m above a large deep-seated gas reservoir on the upper slope of the western Nile deep-sea fan. It has been the object of an integrated study of fluid and gas flow using existing and newly developed observatory technologies to better constrain and quantify devolatilisation and defluidisation patterns and their long-term variability in relation to underlying hydrocarbon reservoirs. As it is known that the activity of mud volcanoes varies significantly over periods of months and weeks, the assessment of the activity of NAMV focuses on proxies of fluid and gas emanations. Submarine mud volcanoes are usually characterized by fluid formation and fluidization processes occuring at depths of several kilometers below the seafloor, driving a complex system of interacting geochemical, geological and microbial processes. Mud volcanoes are natural leakages of oil and gas reservoirs. Near-surface observations made at such sites can therefore be used to monitor phenomena that occur at greater depth. Since the initiation of the project in 2007, NAMV has arguably become one of the best-instrumented mud volcanoes worldwide with a network of observatories collecting long-term records of chemical fluxes, seismicity, temperature, ground deformation, and methane concentration. In addition five research cruises collected complementary geophysical and geological data and samples. In the summer of 2010 a large number of monitoring systems has been recovered which provide us with a synoptic view of the internal dynamics of an active mud volcano. We will present an integrated analysis based on ship-based and sea-floor observations