Magnitude 5.9 Earthquake Shakes Tokyo and Eastern Japan at 2 a.m.
Strong Quake Hits Japan’s Kanto Region
A magnitude 5.9 earthquake struck southern Ibaraki Prefecture in Japan early Sunday, shaking Tokyo and the eastern Kanto region. [1] The quake was centered in southern Ibaraki Prefecture at a depth of 70 kilometers. [1] The United States Geological Survey reported the event as magnitude 5.8 and located it 4 kilometers north of Toride at a depth of 61.0 kilometers. [2] No tsunami threat was issued following the earthquake. [1]
Intensity and Effects in Tokyo and Surroundings
A magnitude 5.9 earthquake struck southern Ibaraki Prefecture shaking Tokyo and eastern Japan. — Source: gdelt Shaking reached an intensity of lower 5 on Japan’s seven-point shindo seismic scale in Tokyo’s Adachi Ward as well as in Ibaraki, Saitama and Chiba prefectures. [1] Level 4 shaking was recorded in other areas of Tokyo as well as in Tochigi, Gunma and Kanagawa prefectures. [1] Level 2 long-period ground motion was observed in the city of Kawaguchi in Saitama Prefecture, the city of Urayasu in Chiba Prefecture, and in Tokyo’s Koto and Edogawa wards. [1] Long-period ground motion refers to slow, prolonged shaking that can cause high-rise buildings to sway significantly. [1] At Level 2, people may have difficulty standing, and furniture or other objects may move or fall. [1]
Damage Assessment and Tsunami Status
Authorities in the affected areas were working to confirm whether the quake had caused injuries or damage. [1] A water pipe had ruptured in the Kiyosumi area of Tokyo’s Koto Ward, but it is not yet known if this was caused by the earthquake. [1] There was no threat of a tsunami. [1]
Other Global Seismic Activity
Separately, a magnitude 4.7 earthquake occurred 170 kilometers southwest of Sungai Penuh, Indonesia, at a depth of 26.3 kilometers. [3] A swarm of small quakes struck California’s Coso volcanic field, with seven tremors detected near Coso Junction by Friday afternoon and the strongest registering a magnitude of 3.4 at 10:26 a.m. PT. [4] The Coso volcanic field is located about 100 miles northeast of Bakersfield and covers a 150-square-mile cluster of volcanic features powered by a large zone of underground magma. [4]
Background on California’s Coso Volcanic Field
The area contains dozens of vents and domes as well as active geothermal fields, fumaroles and hot springs. [4] Recent earthquake activity at Coso is not unusual, as the region has experienced swarms before, often as distant aftershocks triggered by larger earthquakes in the surrounding area. [4] Large tremors such as the magnitude 7.1 Ridgecrest earthquake in 2019 have previously set off hundreds of smaller quakes at Coso. [4] Despite the ongoing seismic activity, the California Volcano Observatory has stated there is currently no evidence of ground deformation or other indicators that would suggest an imminent volcanic eruption. [4] The volcano alert level remains at normal, and the aviation color code is green. [4] Scientists will continue to monitor the situation carefully, watching for any changes that could signal increased volcanic risk. [4] The Coso volcanic field’s most recent eruption occurred tens of thousands of years ago, and while the region remains geologically active, eruptions are considered unlikely in the near future. [4] With its history of producing both rhyolitic lava domes and basaltic flows, experts emphasize the importance of ongoing monitoring. [4]
What to watch next: Scientists will continue to monitor the Coso volcanic field for any changes that could signal increased volcanic risk while authorities in Japan complete checks for injuries or damage from the main event.
