Strong M6.1 earthquake hits Hokkaido, Japan

A magnitude 6.1 earthquake struck Hokkaido, Japan, with its epicenter located 18 kilometers west of Sarabetsu. The quake occurred at a depth of approximately 80 kilometers, affecting a broad area including nearby cities such as Obihiro, Otofuke, and Urakawa. An estimated 4.2 million people experienced light shaking, while around 339,000 felt moderate tremors. Authorities confirmed there was no tsunami threat following the event. The United States Geological Survey (USGS) issued a Green alert, indicating a low likelihood of casualties and significant damage due to the region's generally earthquake-resistant infrastructure. However, some vulnerable structures, particularly those made from adobe block and unreinforced brick with mud, remain at risk. Secondary hazards such as landslides and liquefaction were triggered in limited areas, though the population exposed to these effects is relatively small. Past earthquakes in Hokkaido have occasionally caused fires and landslides, which may exacerbate losses. This earthquake follows a more powerful magnitude 7.4 quake off the coast of Iwate earlier in the month, which generated a tsunami warning and an 80-centimeter wave at Kuji Port. The recent seismic activity highlights the ongoing tectonic volatility in northern Japan, underscoring the importance of preparedness and resilient construction in the region. Despite the moderate intensity of the latest quake, the event serves as a reminder of the persistent seismic risks facing Hokkaido and surrounding areas.