Across the past 11 days, a little-known chain of islands in southwestern Japan has faced an alarming sequence of earthquakes, with over 800 tremors reported, including a notable 5.6-magnitude quake on Wednesday. The Tokara Islands, a collection of 12 islands situated between Japan's main island and Okinawa, have seen shaking more frequent than the number of their inhabitants. The U.S. Geological Survey confirmed the recent quake, while the Japan Meteorological Agency has logged a total of 870 quakes since June 21, with all registering at least 1.5 on its seismic intensity scale.
This unusual uptick in seismic activity is challenging for the islands’ small population of more than 600 residents, many of whom are struggling with sleep deprivation due to the constant tremors. Known for their volcanic origins and natural hot springs, the islands have experienced similar seismic events in the past, but not of this magnitude or frequency.
The cause of this seismic disturbance is yet to be determined, although history suggests that small earthquakes can precede the emergence of new volcanic formations. An example includes a minor island that appeared off Iwo Jima in 2021 following an undersea volcanic eruption.
Despite Japan's extensive preparedness for earthquakes, the isolated nature of the Tokara Islands complicates emergency responses. Reaching Nakanoshima, the largest island, requires a ferry ride exceeding six hours or aerial support from helicopters. Locals on Akusekijima shared their distress with The Asahi Shimbun, indicating sleepless nights due to the tremors. Fortunately, officials have reassured residents that there is no imminent tsunami threat; however, they have advised caution regarding potential landslides and falling debris.
