@article {RN97,
	title = {Volcanic Tremor of Mt. Etna (Italy) Recorded by NEMO-SN1 Seafloor Observatory: A New Perspective on Volcanic Eruptions Monitoring},
	journal = {Geosciences},
	volume = {9},
	number = {3},
	year = {2019},
	pages = {115},
	type = {Journal Article},
	abstract = {The NEMO-SN1 seafloor observatory, located 2100 m below sea level and about 40 km from Mt. Etna volcano, normally records a background seismic signal called oceanographic noise. This signal is characterized by high amplitude increases, lasting up to a few days, and by two typical 0.1 and 0.3 Hz frequencies in its spectrum. Particle motion analysis shows a strong E-W directivity, coinciding with the direction of sea waves; gravity waves induced by local winds are considered the main source of oceanographic noise. During the deployment of NEMO-SN1, the vigorous 2002{\textendash}2003 Mt. Etna eruption occurred. High-amplitude background signals were recorded during the explosive episodes accompanying the eruption. The spectral content of this signal ranges from 0.1 to 4 Hz, with the most powerful signal in the 0.5{\textendash}2 Hz band, typical of an Etna volcanic tremor. The tremor recorded by NEMO-SN1 shows a strong NW-SE directivity towards the volcano. Since the receiver is underwater, we inferred the presence of a circulation of magmatic fluids extended under the seafloor. This process is able to generate a signal strong enough to be recorded by the NEMO-SN1 seafloor observatory that hides frequencies linked to the oceanographic noise, permitting the offshore monitoring of the volcanic activity of Mt. Etna.},
	keywords = {Mt. Etna volcano, oceanographic noise, volcanic monitoring by seafloor observatories, volcanic tremor},
	doi = {10.3390/geosciences9030115},
	url = {https://app.dimensions.ai/details/publication/pub.1112570519 https://www.mdpi.com/2076-3263/9/3/115/pdf},
	author = {Sgroi, Tiziana and Di Grazia, Giuseppe and Favali, Paolo}
}
