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USGS

By Michael Marshall

A large earthquake has struck off the coast of Alaska. A tsunami warning was issued for the US west coast, but has since been cancelled after no significant tsunami materialised.

Initial reports of the earthquake’s magnitude were conflicting, but the US Geological Survey now states it was magnitude 7.9. It struck 280 kilometres south-east of Kodiak, Alaska, at a depth of 25km.

The initial tsunami alert was issued by the Pacific Tsunami Warning Center. It said the tsunami “could be destructive on coastal areas even far from the epicenter”.

A more detailed alert was then posted by the National Tsunami Warning Center. Tsunami warnings were put in effect for British Columbia, South-East Alaska, South Alaska, the Alaska Peninsula and the Aleutian Islands. California, Oregon and Washington were also placed on tsunami watch, a lower level of alert. However, a tsunami watch for the state of Hawaii was soon cancelled. The NTWC has since cancelled all the remaining tsunami alerts.

There have been no reports of significant damage. At 02:29 local time, the Kodiak Police Department reported that water was receding from the harbour, which can be a sign of an imminent tsunami. However, at 03:21 the Kodiak Area Emergency Services Organization announced that the tsunami warning had been “downgraded to an advisory“.