Direct measurements (9): Acoustic records
Yasur,
(oct 1993)
Sound is produced by a
volcano
Informations on volcanic activity
What is the source of the sound?
source = gas
Frequency = size of the source
Amplitude = overpressure
Phase = initial
condition
ejecta velocity
Evolution in time of the eruption characteristics
recording sound waves is a way to monitor volcanic activity
Microbarograph
at Yasur
(oct 2002)
