A team of researchers from the Etna Observatory of the National Institute of Geophysics and Volcanology (INGV - OE) and the GeoForschungsZentrum (GFZ, Germany) has completed the installation of a 1,5 km fiber optic cable on Etna . The aim of the experiment is to test DAS (Distributed Acoustic Sensing) technology, which uses optical fiber as a distributed seismic sensor, to monitor the activity of Europe's largest volcano.
This is the first project using this technology on an active volcano providing data at unprecedented spatial resolution. The fiber optic cable installed on Etna is interrogated by an optical reflectometer (Silixa iDAS) installed at the Pizzi Deneri Observatory; the DAS measurements are validated by a set of 30 broadband seismometers and 3 infrasonic sensor arrays made available by the geophysical instrument pool of the GFZ Potsdam (GIPP).
The instrumentation, installed at an altitude of 2.800 meters, about 550 meters below the summit of Etna, will remain in acquisition until the end of September 2019, and will allow the detection, location and quantification of the deformation generated by seismic-acoustic signals along the cable allowing the structural characterization of the subsoil and dynamic processes in progress and the monitoring of seismic and volcanic activity.
Immediately after the installation, which took place at the beginning of July, Etna resumed its activity with Strombolian explosions and ash emissions from the summit craters, offering researchers a unique opportunity to test for the first time the effectiveness of the monitoring of the eruptive activity through a fiber optic cable.
GALLERY – The working group on the experiment with optical fibers on Etna of the Etnean Observatory of INGV (INGV – OE) and of the GeoForschungsZentrum (GFZ)