Earthquakes have been occurring frequently off the western coast of Jeju recently.
According to the Korea Meteorological Administration (KMA), an earthquake of magnitude 2.6 occurred at approximately 8:35 p.m. the previous evening in waters 128 kilometers west of Jeju City on Monday.
This was the sixth earthquake recorded in Jeju waters this month. The seismic activity began with a magnitude 2.3 earthquake at 3:19 a.m. on November 3 in waters 130 kilometers west of Jeju City. Subsequent earthquakes were detected on November 8, 10, and 14.
Notably, five earthquakes have been concentrated in waters approximately 130 kilometers west of Jeju City. Aside from a magnitude 2.0 earthquake at 4:21 a.m. on November 14, 80 kilometers northeast of Seogwipo City near Ieodo, all other events were localized to this area.
Fortunately, all earthquakes were of magnitude 3.0 or below, meaning they were not strong enough to be felt on the mainland and caused no significant damage.
Historically, Jeju has been considered a safe zone for earthquakes, as seismic activity in nearby waters has been rare.
In the past five years, Jeju waters have recorded 24 earthquakes of magnitude 2.0 or higher. While no earthquakes were detected in 2020, there were three in 2021, six in 2022, three in 2023, and 12 in 2024.
Only two earthquakes of magnitude 4.0 or higher have occurred in Jeju waters in the past 30 years since 1994. These include a magnitude 4.2 earthquake on May 31, 2008, in waters 78 kilometers west of Jeju City and a magnitude 4.9 earthquake (maximum intensity V) on December 14, 2021, in waters 41 kilometers southwest of Seogwipo City.
The rarity of earthquakes in Jeju, coupled with their recent concentration in a specific area over a short period, has drawn significant attention.
A Jeju Regional Meteorological Office official explained, “Earthquakes typically occur along fault lines, but no significant fault line activity has been detected in the seabed of Jeju waters where recent seismic activity is concentrated.” The official further noted that with the rising frequency of earthquakes, “We plan to enhance monitoring efforts to ensure timely detection and analysis.”