The 1946 Unimak Island, Alaska earthquake occurred on 1 April 1946. According to the USGS Earthquake Catalog, the earthquake had a magnitude of 8.6 and a depth of 15.0 kilometers.
The earthquake's magnitude is classified as ‘great' due to its high value. The depth of the earthquake is considered ‘very shallow' since it is less than 20 kilometers.
Historical data on the earthquake is limited, but it is known to have triggered a tsunami flag in the catalog. However, it is essential to note that a tsunami flag does not necessarily mean that a tsunami was observed or that there were any impacts.
It is also worth noting that the earthquake's status is classified as ‘automatic,' indicating that the event was detected and recorded by the USGS Earthquake Catalog without human intervention.
Sources and further context
Official datasets support the event-specific facts.