Moderate mag. 5.5 earthquake - 123 Km NNE of Atka, Alaska, USA, on 27 Oct 4:13 pm (GMT -12) -

Moderate mag. 5.5 earthquake  - 123 Km NNE of Atka, Alaska, USA, on 27 Oct 4:13 pm (GMT -12)

Moderate magnitude 5.5 earthquake at 233 km depth

28 Oct 04:23 UTC: First to report: GFZ after 9 minutes.
28 Oct 04:26: Now using data updates from USGS
28 Oct 04:30: Magnitude recalculated from 5.2 to 5.4. Hypocenter depth recalculated from 254.0 to 234.0 km (from 158 to 145 mi). Epicenter location corrected by 41 km (25 mi) towards NNW.
28 Oct 04:47: Magnitude recalculated from 5.4 to 5.5. Hypocenter depth recalculated from 234.0 to 233.2 km (from 145 to 145 mi). Epicenter location corrected by 2.6 km (1.6 mi) towards SE.
Date & time: 28 Oct 2020 04:13:41 UTC -
Local time at epicenter: 27 Oct 4:13 pm (GMT -12)
Magnitude: 5.5
Depth: 233.2 km
Epicenter latitude / longitude: 53.2014°N / 173.4182°W (Alaska, United States)
Nearest volcano: Korovin (105 km / 65 mi)
Nearby towns and cities:
263 km (163 mi) NE of Adak (pop: 332)
306 km (190 mi) W of Nikolski (pop: 18)
461 km (286 mi) W of Unalaska (pop: 4,490)
514 km (319 mi) W of Akutan (pop: 1,040)
678 km (422 mi) WSW of False Pass (pop: 40)
729 km (453 mi) WSW of Cold Bay (pop: 123)
2469 km (1534 mi) W of Juneau (pop: 32,800)
Weather at epicenter at time of quake:
Light Rain 7.6°C (46 F), humidity: 97%, wind: 4 m/s (8 kts) from SW
Primary data source: USGS
Estimated released energy: 1.1 x 1013 joules (3.12 gigawatt hours, equivalent to 2682 tons of TNT or 0.2 atomic bombs!) More info
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Data for the same earthquake reported by different agencies

Info: The more agencies report about the same quake and post similar data, the more confidence you can have in the data. It takes normally up to a few hours until earthquake parameters are calculated with near-optimum precision.
M 5.5233 km123 Km NNE of Atka, Alaska, USAUSGS
M 5.5238 kmAndreanof Islands, Aleutian Is., USAEMSC
M 5.4235 km98 Km NE of Atka, Alaska, USAGFZ
M 5.5236 kmAndreanof Islands, Aleutian Islands, USAGeoAu
M 5.3244 kmAndreanof Islands, Aleutian Islands, USABMKG

User reports for this quake

User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
There are no user reports for this quake yet. If you felt it be the first to report it!
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Aftershocks of the 5.5 quake 123 Km NNE of Atka, Alaska, USA, 27 Oct 4:13 pm (GMT -12)

More info
Recorded aftershocks, latest first (0 quakes):
So far, no aftershocks have been registered.

Earlier earthquakes in the same area since 1900

Moderate mag. 5.5 earthquake - 123 Km NNE of Atka, Alaska, USA, on 27 Oct 4:13 pm (GMT -12)

Map of earlier quakes

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