The origin of volcanic tremor is still the subject of vigorous scientific debate. One of the most recent models, by Ripepe and Gordeev, suggests that volcanic tremor is related to the coalescence of bigger gas bubbles from a layer of smaller ones in the magma foam, forced by a structural barrier. The evidence of this model is mainly related to the relationship between the seismic signal and infrasonic waves. These must be generated by the same dynamical process, although the latter are related to a successive phase, i.e. the bursting of the bubbles at the magma-air interface.
Previous studies by Carniel and Di Cecca furnished evidence that volcanic tremor can be considered as a state variable of a deterministic dynamical system of "low" dimension. If the pressure signal is related to the same dynamical process, the two time series should not show too different dynamical behaviour.
On 19 June 1999, an experiment was carried out, recording simultaneously not only seismic and pressure waves, but also thermal data, using a Minolta/Land Cyclops 330 infrared thermometer aimed at one of the vents in NE Crater. Preliminary results from the dynamical analysis of the resulting time series are presented and discussed.
