Chocolate-chip cookie-like pumice from the 2021 Fukutoku-Oka-no-Ba eruption: views from SNS-related geology

Abstract

Pumice ejected from the Fukutoku-Oka-no-Ba (FOB) eruption of August 2021 arrived at the Nansei Islands after 2-months drifting, and subsequently arrived at Kanto area to the east and Taiwan, Philippines, and Thailand to the west. Deposition of huge amount of the drift pumice, most of which had a chocolate-chip cookie resemblance in appearance, is a drastic event and thus attracted SNS account holders, so that the arrival timeline can be traced via their daily posts. Gathering such huge amount of information from the internet can be a powerful tool to investigate and predict a geologic phenomenon that aŠects wide area in a short time scale. We introduce the drift pumice from FOB with respect to their deposition style, petrographic characteristics, and comparison with the previous drift pumice phenomena observed in Japan. Their impact to the Japanese society was well re‰ected to the buzz on Twitter. Finally, we discuss how the scientist should behave on the internet to provide correct information in an eŠective way.