Frequent earthquakes release the energy and prevent a mega quake. (Representational image)
Tokyo, May 5: An earthquake measuring 6.3 on the Richter scale struck Japan's Ishikawa prefecture and its surrounding areas on Friday, but there is no threat of a tsunami, the country's weather agency said.
According to the Japan Meteorological Agency (JMA), the temblor occurred at 2.42 p.m. (local time), at a depth of 10 km, registering an upper 6 on the national seismic intensity scale of 7 in the city of Suzu, upper 5 in Noto and lower 5 in Wajima, Xinhua news reported.
The agency said there was no threat of a tsunami, but sea level changes of less than 20 cm were possible.
No abnormalities have been detected at the Shika nuclear power plant in Ishikawa, as well as at the Kashiwazaki-Kariwa nuclear power plant in the neighboring prefecture of Niigata, Kyodo News reported.