Strong M6.4 earthquake hits Shikoku, Japan
Featured image: Image credit: TW/SAM, Google
A strong and shallow earthquake registered by the JMA as M6.4 hit Shikoku, Japan at 16:08 UTC on January 21, 2022. The agency is reporting a depth of 40 km (24.8 miles). EMSC and USGS are reporting M6.3 at a depth of 41.8 km (26 miles).
The epicenter was located 24.3 km (14.1 miles) SSE of Saiki (population 49 065), 38 km (23.6 miles) SSE of Tsukumiura (population 21 658), and 40.4 km (25.1 miles) ENE of Nobeoka (population 121 949), Japan.
There are about 1.7 million living within 100 km (62 miles).
10 000 people are estimated to have felt strong shaking and 520 000 moderate.
There is no tsunami threat from this earthquake.
Image credit: TW/SAM, Google
Image credit: TW/SAM, Google
The USGS issued a Green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage.
Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are heavy wood frame and reinforced/confined masonry construction.
Recent earthquakes in this area have caused secondary hazards such as landslides, fires and liquefaction that might have contributed to losses.
Estimated population exposure to earthquake shaking
Selected cities exposed
Regional seismicity
Teo Blašković founded The Watchers in 2011 and edited it until 2026, covering seismic and volcanic activity, extreme weather, space weather and near-Earth objects. Articles on this page are his archive.
