219 km S of Sand Point, Alaska

This was a moderate earthquake. Shaking at this size can damage poorly built structures close to the epicentre. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 1.9 kilotons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 6.4 would have released about 32 times as much.

1. Northridge, California 1994 M 6.7 89× the energy of this one
2. Mineral, Virginia 2011 M 5.8 4× the energy of this one
3. Magna, Utah 2020 M 5.7 2.8× the energy of this one
4. This earthquake M 5.4 about 1.9 kilotons of TNT
5. Around the size people start to feel M 3.0 this one released 4,000× more

Energy from the Gutenberg–Richter relation (log₁₀E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

Where

Epicentre 53.3650, -160.2941. Map © OpenStreetMap contributors.

Aftershocks so far

59 earthquakes have been recorded within 50 km since this one.

1. 2.3 206 km SSE of Sand Point, Alaska 16:21 UTC
2. 3.2 231 km S of Sand Point, Alaska 03:19 UTC
3. 2.3 206 km S of Sand Point, Alaska 21:31 UTC
4. 2.8 229 km SSE of King Cove, Alaska 00:26 UTC
5. 2.9 235 km S of Sand Point, Alaska 13:03 UTC
6. 2.6 218 km S of Sand Point, Alaska 04:57 UTC
7. 3.2 220 km S of Sand Point, Alaska 15:47 UTC
8. 2.8 223 km S of Sand Point, Alaska 02:19 UTC
9. 2.6 226 km S of Sand Point, Alaska 08:59 UTC
10. 2.4 226 km S of Sand Point, Alaska 11:12 UTC
11. 3.4 193 km SSE of King Cove, Alaska 01:35 UTC
12. 2.8 239 km S of Sand Point, Alaska 03:58 UTC
13. 3.5 223 km S of Sand Point, Alaska 16:37 UTC
14. 2.9 205 km SSE of King Cove, Alaska 10:06 UTC
15. 3.0 223 km S of Sand Point, Alaska 01:42 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 18:02 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 5.5 on 2020-07-05 — it released about 1.4 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

• The official USGS event page — the source of record for every value above
• Did you feel it? Report it to USGS — reports go to USGS, not to us
• ShakeMap for this event, when USGS has produced one

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.