Very strong mag. 6.5 earthquake - Gulf of Alaska, 16 mi south of Sanak Island, Aleutians East County, Alaska, USA, on Sunday, 21 June 1987 at 05:46 (GMT)

Very strong mag. 6.5 earthquake - Gulf of Alaska, 16 mi south of Sanak Island, Aleutians East County, Alaska, USA, on Sunday, 21 June 1987 at 05:46 (GMT)

Very strong magnitude 6.5 earthquake at 34 km depth

Date & time: 21 Jun 1987 05:46:10 UTC
Magnitude: 6.5
Depth: 33.6 km
Epicenter latitude / longitude: 54.211°N / 162.601°W (Gulf of Alaska, Alaska, United States)
Nearest volcano: Roundtop (91 km / 57 mi)
Nearby towns and cities:
89 km (55 mi) SE of False Pass (pop: 40) --> See nearby quakes!
96 km (60 mi) S of King Cove (pop: 1,010) --> See nearby quakes!
109 km (68 mi) S of Cold Bay (pop: 123) --> See nearby quakes!
184 km (114 mi) SW of Sand Point (pop: 1,060) --> See nearby quakes!
207 km (129 mi) E of Akutan (pop: 1,040) --> See nearby quakes!
218 km (135 mi) SSW of Nelson Lagoon (pop: 52) --> See nearby quakes!
260 km (161 mi) E of Unalaska (pop: 4,490) --> See nearby quakes!
290 km (180 mi) SW of Perryville (pop: 113) --> See nearby quakes!
333 km (207 mi) SW of Chignik Lake (pop: 73) --> See nearby quakes!
348 km (216 mi) SW of Chignik Lagoon (pop: 78) --> See nearby quakes!
Primary data source: USGS (United States Geological Survey)
Estimated released energy: 3.5 x 1014 joules (98.6 gigawatt hours, equivalent to 84802 tons of TNT or 5.3 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.
MagnitudeDepthLocationSource
M 6.534 kmAlaska Peninsula (USA)USGS
Note: for quakes of 2012 and earlier, our database often contains only records from USGS.

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

More info
Recorded aftershocks, latest first (6 quakes):
  • 01 Jul 1987 08:39 UTC
    | M 4.6 |
    33 km (20.5 mi) depth
    |
    20 km (12 mi) distance
    | USGS | Details
  • 29 Jun 1987 09:55 UTC
    | M 4.6 |
    33 km (20.5 mi) depth
    |
    76 km (47 mi) distance
    | USGS | Details
  • 22 Jun 1987 05:15 UTC
    | M 4.2 |
    33 km (20.5 mi) depth
    |
    49 km (31 mi) distance
    | USGS | Details
  • 21 Jun 1987 07:51 UTC
    | M 4.9 |
    33 km (20.5 mi) depth
    |
    7 km (4 mi) distance
    | USGS | Details
  • 21 Jun 1987 06:18 UTC
    | M 4.8 |
    33 km (20.5 mi) depth
    |
    12 km (7 mi) distance
    | USGS | Details
  • 21 Jun 1987 05:55 UTC
    | M 5.5 |
    33 km (20.5 mi) depth
    |
    8 km (5 mi) distance
    | USGS | Details

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Earlier earthquakes in the same area

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