A series of field measurements of seismic signals detected at the volcano Stromboli has been made during 1935 and 1986. Data were collected both during periods of standard activity and during the eruption of Dec. 1985. Simultaneous records have been obtained using both analogical portable stations equipped with 1 Hz vertical seismometers and digital three component short period stations of the University of Clermont Ferrand. Features o-f seismic signals typically recorded at Stromboli, such as volcanic tremor and low-frequency events have been investigated and in particular, two main groups of seismic events have been found. Some events are monochromatic with dominant frequencies in the range 1-3 Hz, while a second group of seismic events show two main phases, the first having low frequencies (< 2 Hz) and the second one at higher frequency values (3 ≤ f < 6 Hz). The observation o-f stability and repeativity of spectral frequency peaks, together with the lack of harmonics both in the spectra of volcanic tremor and l.f. events, allowed to interpret such signals as due to a common source. Moreover, an attempt has been made to model the main feeding ducts of the volcano.
|Titolo:||Segnali sismici a Stromboli e loro caratteristiche|
|Data di pubblicazione:||1988|
|Appare nelle tipologie:||4.1 Contributo in Atti di convegno|