A new study carried out by the Geosciences Barcelona researcher of the Higher Council for Scientific Research (GEO3BCN-CSIC) Jordi Díaz analyzes the various types of seismic signals generated by the submarine volcanic explosion of the Hunga Tonga-Hunga Ha’apai and provides new details about the phenomena that occurred in this geological event.
On January 15, 2022, the Hunga-Tonga volcano, located in the Pacific Ocean, erupted causing one of the volcanic events largest in recent history. “The volcanic explosion caused the Earth to vibrate at very low frequencies, ringing for about 8 hours“, explains Díaz. This record of low-frequency resonant signals, clarifies the researcher, had only been previously detected after the eruptions of Pinatubo (Philippines, 1991) and El Chichón (Mexico, 1982).
In this new article, published in the magazine Communications Earth & Environment from the Nature group, Díaz focuses on the temporal evolution of the eruptive processthe propagation of atmospheric waves around the Earth, and low-frequency seismic signals and long term worldwide after the main event.
According to the GEO3BCN-CSIC scientist, it is the first time registering with seismometers the passage of the atmospheric wave for such a long time: “The pressure wave was so powerful that, even after going around the Earth twice it still manages to vibrate the ground and be detected by a seismometer“. Seismic networks identified the passage of this wave up to five times over three and a half days.
“The work is further proof that seismometers not only allow earthquakes to be detected, but that they can be useful for detecting other types of signals“says the Geosciences Barcelona scientist in a statement.
The variation in atmospheric pressure generated by this explosion spread throughout the planet, producing variations that were detected by various types of sensors. “To carry out the work, seismic data have been collected from the main networks Worldwideas well as stations of the networks of the Institut Cartogràfic i Geològic de Catalunya and the National Geographic Institute”, details Díaz.