[Previous] | [Session 46] | [Next]
A. D. Fortes, P. M. Grindrod (Dept. Earth Sciences, University College London, Gower St, London, WC1E 6BT, UK)
Mud volcanoes are a common sub-aerial and submarine phenomenon on the Earth. They typically occur in association with thick sequences of rapidly accumulated sediments, containing overpressured, undercompacted, layers of soft mud overlain by denser material. Titan is perhaps the only other place in the solar system where conditions appropriate for the formation of mud volcanoes may prevail. Recent data from the Cassini-Huygens mission indicates the presence of widespread low-lying regions filled with organic sediments and saturated with liquid methane. Assuming a nominal regolith composed primarily of water ice with varying amounts of acetylene, which at 100 K have densities of 930 and 770 kg m-3 respectively, and a pure acetylene mud source at up to 1000 m depth, we investigate the possible dimensions of mud volcanoes on Titan. Using a simple isostatic model, we find that mud volcanoes on Titan could be of the order of 100 to 200 m in height. Applying a simple eruption model, and assuming similar dynamic viscosity, eruption duration and conduit radius values to terrestrial mud volcanoes, we find that the diameter of mud volcanoes on Titan could be of the order of 1000 to 2000 m, giving a broad domical profile. Therefore, the construction of modestly-sized mud volcanoes on Titan is a feasible proposition. We would also argue that their occurrence is favoured where relatively dense ice-rich soils overlie lower density organic sediments; in the ejecta blankets of impact craters, for example. We would also expect mud volcanoes to occur in association with cryovolcanic vents erupting water (or ammonia-water mixtures) from deeper melt sources. The authors acknowledge funding from the Particle Physics and Astronomy Research Council (PPARC).
[Previous] | [Session 46] | [Next]
Bulletin of the American Astronomical Society, 37 #3
© 2004. The American Astronomical Soceity.