Nonlinear Processes in Geophysics www.nonlin-processes-geophys.net 1023-5809 1607-7946 17 2 2010 10.5194/npg-17-221-2010 http://www.nonlin-processes-geophys.net/17/221/2010/ http://www.nonlin-processes-geophys.net/17/221/2010/npg-17-221-2010.html http://www.nonlin-processes-geophys.net/17/221/2010/npg-17-221-2010.pdf 221 235 2010-04-20 The effect of volatile bubble growth rate on the periodic dynamics of shallow volcanic systems I. L'Heureux ilheureu@uottawa.ca Ottawa-Carleton Institute of Physics and Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N6N5, Canada Many volcanic eruptions exhibit periodic behavior. For instance, periodic ground inflations and deflations in proximity to a volcano are the consequences of periodic overpressure variations in the magma conduit and periodic magma flow rate. The period varies from a few hours to many years, depending on the volcano parameters. 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