Mag. 4.7 earthquake - 71 mi southeast of Sand Point, Aleutians East County, Alaska, on 21 Oct 12:56 am (GMT -11) -
This quake was likely an aftershock of the 7.6 quake Gulf of Alaska, 60 mi southeast of Sand Point, Aleutians East County, Alaska, USA, 19 Oct 2020 11:54 am (GMT -9), which had occurred 1 day 15 hours earlier.
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Light magnitude 4.7 earthquake at 19 km depth
21 Oct 12:09 UTC: First to report: GFZ after 13 minutes.
21 Oct 12:10: Now using data updates from USGS
21 Oct 12:10: Now using data updates from USGS
Local time at epicenter: 21 Oct 12:56 am (GMT -11)
Magnitude: 4.7
Depth: 18.8 km
Epicenter latitude / longitude: 54.4427°N / 159.6231°W
(Gulf of Alaska, United States)Nearest volcano: Stepovak Bay 2 (166 km / 103 mi)
Nearby towns and cities:
114 km (71 mi) SSE of Sand Point (pop: 1,060) --> See nearby quakes!
166 km (103 mi) S of Perryville (pop: 113) --> See nearby quakes!
186 km (116 mi) ESE of King Cove (pop: 1,010) --> See nearby quakes!
200 km (124 mi) SSE of Nelson Lagoon (pop: 52) --> See nearby quakes!
209 km (130 mi) SSW of Chignik Lake (pop: 73) --> See nearby quakes!
215 km (134 mi) ESE of Cold Bay (pop: 123) --> See nearby quakes!
219 km (136 mi) SSW of Chignik Lagoon (pop: 78) --> See nearby quakes!
401 km (249 mi) E of Akutan (pop: 1,040) --> See nearby quakes!
6151 km (3822 mi) NW of Washington DC (pop: 601,700) --> See nearby quakes!
6151 km (3822 mi) NW of Washington DC (pop: 601,700) --> See nearby quakes!
38 km (24 mi) S of Chernabura Island --> See nearby quakes!
Weather at epicenter at time of quake:
Overcast Clouds
7.7°C (46 F), humidity: 76%, wind: 13 m/s (25 kts) from E
Primary data source: USGS (United States Geological Survey)
Overcast Clouds
7.7°C (46 F), humidity: 76%, wind: 13 m/s (25 kts) from EEstimated released energy: 7.1 x 1011 joules (197 megawatt hours, equivalent to 169 tons of TNT) More info
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.
| Magnitude | Depth | Location | Source |
| M 4.7 | 19 km | 114 Km SSE of Sand Point, Alaska, USA | USGS |
| M 4.7 | 30 km | South of Alaska, USA | GFZ |
| M 4.7 | 20 km | South Of Alaska, USA | EMSC |
User reports for this quake (1)
User reports estimate the perceived ground shaking intensity according to the MMI (Modified Mercalli Intensity) scale.
Pomona CA / Light shaking (MMI IV) / rattling, vibrating / 5-10 s
Earlier earthquakes in the same area
Mag. 4.7 earthquake - 71 mi southeast of Sand Point, Aleutians East County, Alaska, on 21 Oct 12:56 am (GMT -11)
Click here to search our database for earlier earthquakes in the same area since 1900!
