Magnitude 6.9 quake hits Kamchatka; Japan withdraws erroneous alert

A magnitude 6.9 earthquake struck the Kamchatka region in Russia’s Far East on Friday, October 16, according to the US Geological Survey. Japan subsequently withdrew an erroneous warning that had greatly overstated the earthquake’s strength.

The USGS placed the tremor at about 3.35 am UTC and estimated its depth at 135 kilometres. The European-Mediterranean Seismological Centre initially measured the earthquake at magnitude 7 before revising its estimate to 6.9.

Depth estimates also varied as the measurements were updated. The European centre’s later figure was 130 kilometres, compared with an initial estimate of 140 kilometres.

The centre placed the epicentre roughly 146 kilometres south-southwest of Petropavlovsk-Kamchatsky and 80 kilometres north-northeast of Ozernovskiy. Information about damage or casualties was not immediately available.

US tsunami monitoring agencies said the earthquake posed no tsunami threat. The National Oceanic and Atmospheric Administration issued no warning, advisory or watch following the tremor.

In Japan, an early warning mistakenly displayed an estimated magnitude of 9.9 and identified the Kuril Islands region as the location. It predicted strong shaking across northern, eastern and central parts of the country.

The alert went out at 12.36 pm Japanese local time, triggering alarms on mobile phones and public loudspeakers. It was cancelled at 12.48 pm after the Japan Meteorological Agency determined that the earthquake’s magnitude had been overestimated.

The actual earthquake caused no shaking in Japan. The mistaken warning and the subsequent cancellation were separate from the US agencies’ assessment that there was no tsunami danger.

Kamchatka lies along the Pacific Ring of Fire, a tectonically active belt surrounding much of the ocean. Earthquakes and volcanic activity occur frequently along this part of Russia’s Pacific coast.