Japan’s Hokkaido region experienced two undersea earthquakes near Nemuro in the early hours of Sunday. According to the German Research Centre for Geosciences (GFZ), a 6.1 magnitude earthquake struck off the coast of Hokkaido on Saturday, June 21, 2025, at 21:23 UTC (2:53 AM local time). The earthquake occurred at a shallow depth of 10 kilometers, intensifying potential impact in the area. The United States Geological Survey (USGS) later confirmed and reviewed the quake, locating it 88 kilometers east-southeast of Nemuro. No public damage or injuries have been reported as of now.
Another Tremor Recorded Minutes Later Near Nemuro
Just 30 minutes after the 6.1 magnitude earthquake, a second tremor of 4.3 magnitude struck 99 kilometers southeast of Nemuro. This smaller quake occurred at 21:53 UTC (3:23 AM local time), according to the USGS. It originated at a depth consistent with the earlier quake, continuing the seismic activity in the offshore region. The magnitude type for this second quake was recorded as “mb” and also received official review by seismologists. Authorities have received no public reports of the second quake, and no tsunami warning has been issued so far.
Seismologists Monitor Activity; No Damage Reported
Both seismic events were reviewed by experts and published by the USGS with active monitoring in place. While no injuries or damage have been reported yet, the back-to-back nature of these tremors has prompted a closer watch on the region. Hokkaido, located in Japan’s seismically active zone, regularly experiences tectonic shifts due to its proximity to major fault lines in the Pacific Ring of Fire. Local authorities and the Japan Meteorological Agency continue to assess the situation and reassure the public regarding safety.
