The strongest volcanic earthquake on record just hit Italy's Campi Flegrei volcano, damaging dozens of structures and causing rubble to fall onto some streets. Yet, the earthquake which did strike was only a M4.7. Today's video discusses why only a modest magnitude earthquake caused such noteworthy damage, and why this in my opinion does NOT indicate that Campi Flegrei will erupt anytime soon. Thumbnail Photo Credit: Keaton Terry, Used with Permission Note: I am not telling people to intensely worry about the damage Campi Flegrei’s volcano tectonic earthquakes might cause. Rather, I’m saying that in my opinion it’s far more likely of a potential threat than a volcanic eruption in the next several decades. For this video's title, it is referring to the M4.7 being the strongest volcanic earthquake to strike the Campi Flegrei volcano since seismometers were added. A special thanks to the EarthquakeSim YouTube channel for granting me permission to use clips of his footage! Video Sources from the EarthquakeSim YouTube channel: [1] https://www.youtube.com/watch?v=cjpQryJnHTc [2] https://www.youtube.com/watch?v=RWHNmUbGXv4 Subscribe to EarthquakeSim at: https://www.youtube.com/@EarthquakeSim If you would like to support this channel, consider using one of the following links: (Patreon: http://patreon.com/geologyhub) (YouTube membership: https://www.youtube.com/channel/UCYeGh5VML5XPr5jYnzh3J6g/join) (Gemstone & Mineral Etsy store: http://prospectingarizona.etsy.com) (GeologyHub Merch Etsy store: http://geologyhub.etsy.com) Google Earth imagery used in this video: ©Google & Data Providers This video is protected under "fair use". If you see an image and/or video which is your own in this video, and/or think my discussion of a scientific paper (and/or discussion/mentioning of the data/information within a scientific paper) does not fall under the fair use doctrine, and wish for it to be censored or removed, contact me by email at [email protected] and I will make the necessary changes. Various licenses used in sections of this video (not the entire video, this video as a whole does not completely fall under one of these licenses) and/or in this video's thumbnail image (and this list does not include every license used in this video and/or thumbnail image): Public Domain: https://creativecommons.org/publicdomain/mark/1.0/ CC BY 4.0: https://creativecommons.org/licenses/by/4.0/legalcode Sources/Citations: [1] INGV [2] Tan, Xing & Tramelli, Anna & Gammaldi, Sergio & Beroza, Gregory & Ellsworth, William & Marzocchi, Warner. (2025). A clearer view of the current phase of unrest at Campi Flegrei caldera. Science (New York, N.Y.). 390. eadw9038. 10.1126/science.adw9038. [3] Iaccarino, A. G., Picozzi, M., De Landro, G., & Spallarossa, D. (2025). Preparatory phase of major earthquakes during Campi Flegrei unrest (2020–2024). Journal of Geophysical Research: Solid Earth, 130, e2025JB031777. https://doi.org/10.1029/2025JB031777, CC BY 4.0. [4] VEIs, dates/years, composition, tephra layer name, DRE estimates, and bulk tephra volume estimates for volcanic eruptions shown in this video which were assigned a VEI 4 or larger are sourced from the LaMEVE database (British Geological Survey © UKRI), https://www2.bgs.ac.uk/vogripa/view/controller.cfc?method=lameve, Used with Permission [5] Source of Volcanic Explosivity Index (VEI) methodology and criteria: Newhall, C. G., and Self, S. (1982), The volcanic explosivity index (VEI) an estimate of explosive magnitude for historical volcanism, J. Geophys. Res., 87(C2), 1231–1238, doi:10.1029/JC087iC02p01231. Accessed / Read by Youtube.com/GeologyHub on Oct 5th, 2022. [6] Kilburn, C.R.J., Carlino, S., Danesi, S. et al. Potential for rupture before eruption at Campi Flegrei caldera, Southern Italy. Commun Earth Environ 4, 190 (2023). https://doi.org/10.1038/s43247-023-00842-1, CC BY 4.0. [7] Di Vito, M., Acocella, V., Aiello, G. et al. Magma transfer at Campi Flegrei caldera (Italy) before the 1538 AD eruption. Sci Rep 6, 32245 (2016). https://doi.org/10.1038/srep32245, CC BY 4.0. [8] Giudicepietro, Flora & Macedonio, Giovanni & Martini, Marcello. (2017). A Physical Model of Sill Expansion to Explain the Dynamics of Unrest at Calderas with Application to Campi Flegrei. Frontiers in Earth Science. 5. 10.3389/feart.2017.00054. CC BY 4.0 [9] Amoruso, Antonella & Crescentini, Luca & D'Antonio, M. & Acocella, Valerio. (2017). Thermally-assisted Magma Emplacement Explains Restless Calderas. Scientific Reports. 7. 10.1038/s41598-017-08638-y., CC BY 4.0 [10] U.S. Geological Survey 0:00 Campi Flegrei Earthquake 2:19 Why it was so Damaging 4:02 Seismic Resonance 5:28 Slow Magma Intrusion 5:45 Earthquake Cause 6:45 Additional Regional Footage