Strong and shallow M7.5 earthquake hits south of Alaska, tsunami warning issued

A strong earthquake registered by the USGS as M7.5 hit south of Alaska at 20:54 UTC (12:54 LT) on October 19, 2020. The agency is reporting a depth of 40 km (25 miles).
The epicenter was located 91.7 km (56.9 miles) SE of Sand Point (population 1 064) and 929.9 km (576.5 miles) SW of Anchorage (population 298 695), Alaska.
There are about 800 people living within 100 km (62 miles).
Based on the preliminary earthquake parameters, hazardous tsunami waves are possible for coasts located within 300 km (186 miles) of the earthquake epicenter, NWS PTWC said 21:04 UTC.
A Tsunami Warning is in effect for South Alaska and the Alaska Peninsula, Pacific coasts from Kennedy Entrance, Alaska (65 km / 40 miles SW of Homer) to Unimak Pass, Alaska (129 km / 80 miles NE of Unalaska).
Chignik Bay, Alaska observed a maximum tsunami height of 76.2 cm (2.5 feet), Sand Point 70 cm (2.3 feet), and King Cove 64 cm (2.1 feet).
A Tsunami Advisory was in effect from 23:06 UTC for South Alaska and the Alaska Peninsula, Pacific coasts from Kennedy Entrance, Alaska (65 km / 40 miles SW of Homer) to Unimak Pass, Alaska (129 km / 80 miles NE of Unalaska).
The advisory was canceled for the coastal areas of South Alaska and the Alaska Peninsula at 05:05 UTC on October 20.
Image credit: TW/SAM, Google
The USGS issued a green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage.
Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are unreinforced brick masonry and reinforced masonry construction.
2 000 people are estimated to have felt strong shaking.
Aftershocks
The USGS registered 38 M2.9 – 5.9 aftershocks by 05:39 UTC on October 20.
Image credit: TW/SAM, Google
Estimated population exposure to earthquake shaking
Selected cities exposed
Regional seismicity
Featured image credit: TW/SAM, Google
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