GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.2 GNGTS 2024 The INGV-laboratory has developed an electro-mechanical device based on a subwoofer, which can be used both as a sensor and as a source for calibraton. In a passive “sensor”-mode the pressure actng on the membrane regulates the current inside the subwoofer’s voice-coil, while in an actve “calibraton”-mode a waveform generator steers the oscillaton of the subwoofer’s membrane, whose amplitude is then controlled by a LVDT-interface. The pressure variatons are then channelized through a hose directly to the sensor input pressure interface. As the desired frequency range is the same as for seismic statons, infrasound signals are recorded by commercial seismic digitzers, as e.g., Nanometrics CENTAUR, Cube or GAIA. The presentaton gives an update of the work in progress and will outline future perspectves. Fig. 1 – Example of an earthquake and rumble located on 22/07/2020 at 19:36 in the area of Montecassino (FR). Note the occurrence of three small seismic events (coloured traces) prior to the infrasound signal (black). References Braun T., Danesi S., and Morelli A.; 2020: Applicaton of monitoring guidelines to induced seismicity in Italy. J. Seis. Braun T. and Ripepe M.; 1993: Interacton of Seismic and Air Waves Recorded at Stromboli Volcano. Geophys. Res. Let., 20(1), 65-68. Garces M. A., McNut S. R., Hansen R. A., Eichelberger J. C.; 2000: Applicaton of wave-theoretcal seismoacoustc models to the interpretaton of explosion and erupton tremor signals radiated by Pavlof volcano, Alaska. J. Geophys. Res., 105(B2), 3039-3058. Hagerty M. T., Schwartz S. Y., Garces M. A., Prot M.; 2007: Analysis of seismic and acoustc observatons at Arenal Volcano, Costa Rica, 1995-1997. J. Volcanol. Geotherm. Res., 101, 27