In my opinion, it appears that a volcanic eruption went unnoticed in a 1st world country, in fairly close proximity to where people live and work. New craters formed in the ground, and a field of fine particulates that looked like ash was scattered across an 80,000 square meter region. And yet, this may not have been a phreatic eruption, despite occurring on the southern flank of the Kirishima volcano. Two other explanations cannot be ruled out, and this video via the analysis of a geologist will discuss all 3 possibilities. Thumbnail Photo Credit: Ryusuke IMURA, @tigers_1964 (on X), https://x.com/tigers_1964/status/2014188392943083589/photo/3, Used with Permission A special thanks to Ryusuke IMURA for granting me permission to use several photos of his! 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 2.0: https://creativecommons.org/licenses/by/2.0/legalcode CC BY 4.0: https://creativecommons.org/licenses/by/4.0/legalcode Sources/Citations: [1] U.S. Geological Survey [2] Yellowstone Volcano Observatory [3] Japanese Meteorological Agency [4] 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. 0:00 Unnoticed Volcanic Eruption? 0:25 Kirishima Volcano 0:54 Phreatic Eruptions? 3:01 Hydrothermal Explosions? 4:20 Ash Producing Fumaroles?