March 9, 1957 Earthquake: Alaska, United States

The source of this earthquake and tsunami was to the south of the Andreanof Islands. There were no victims. Judging by the size of the zone of the epicenters of the numerous aftershocks, the source of the earthquake was stretched out in an arc for more than 600 km, bounded on the west by Amchitka Pass and on the east by the Unimak Pass.

On Adak Island, the earthquake and tsunami did great damage. Cracks appeared in the roads. Some of these cracks according to accounts, were up to 5 m wide; structures were destroyed, as well as two bridges. Many piers suffered serious damage. According to reports, an 8-meter was was observed in Sand Bay.

Mount Vsevidof (volcano), which had been dormant for 200 years, became active.

The tsunami, spreading along the entire Pacific, caused damage or was observed visually on the Hawiian Islands, Japan and on the cosst of North and South America. (all from Reference #414)

March 9, 1957, 14:22:31.9 UTC, 51.292 N, 175.629 W, depth 33 km, magnitude 8.1 MS. 8.82 moment, intensity VIII. Andreanof Islands, Aleutian Islands, Alaska. This great earthquake destroyed two bridges on Adak Island, damaged houses, and left a 4.5-m crack in a road. On Umnak Island, part of a dock was destroyed, and Mount Vsevidof erupted after being dormant for 200 years. Further, this shock generated a 15-m tsunami that smashed into the coastline at Scotch Cap and an 8-m tsunami that washed away many buildings and damaged oil lines extensively at Sand Bay. This tsunami continued to Hawaii, where it destroyed two villages and inflicted about $5 million in property damage on Oahu and Kauai Islands. The tsunami also caused minor damage in San Diego Bay, Calif., before traveling to such distant countries as Chile, El Salvador, Japan, and other areas in the Pacific region. More than 300 aftershocks were reported along the southern edge of the Aleutians, from Unimak Island to Amchitka Pass. (reference #542)

March 9, 1957, magnitude 8.25 MS, 9.1 Mw (reference #1314)

March 9, 1957, 14:22:28 UTC, 51.3 N, 175.8 W, shallow depth, magnitude 8.25 MS. (reference #88)

March 8, 1957, magnitude 8.6. (reference #4035)

1957, March 9, 14:22:32.6 UTC, 51.556 N, 175.392 W, 30 km depth, 9.1 M GSX, 8.6 Mw P&S, 8.1 Ms ABE1. (reference #9910)

1957, March 9, 14:22:33 UTC, 51.499 N, 175.626 W, 25 km depth, 8.6 Mw (reference #13456, access date 2023)

1957, March 9, 14:22:33.58 UTC, 51.499 N, 175.626 W, 25 km depth, 8.56 Mw (reference #10476, v.10)