QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

Earthquake near Deltana, AK

USGS: 17 km SSW of Deltana, Alaska

11:54 pm AKDT, Mar 15, 2021 · · 19 km deep · released about 15 lb of TNT

Every earthquake near Deltana Felt it? Tell USGS Check my area
10 km30 km60 km120 km N Southeast Fairbanks Census Area 104 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
11:54 pm AKDT on 15 March 2021 ()
Where
17 km (11 mi) SSW of Deltana, AK · earthquakes near Deltana
Magnitude
M 1.8 (ml)
Depth
19 km below the surface
Felt
1 report · strongest reported intensity II
Nearest
Southeast Fairbanks Census Area, 104 km E
Nearest mapped fault
Granite Mountain fault (Northern Foothills fold and thrust belt), 6 km from its surface trace — near is not the same as on
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 2003 days ago

A magnitude 1.8 earthquake was recorded 17 km (11 mi) SSW of Deltana, AK, at 11:54 pm AKDT on 15 March 2021 (07:54 UTC). 1 person has reported feeling it to USGS. This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 15 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,000,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 710,000× the energy of this one
  3. Around the size people start to feel M 3.0 63× the energy of this one
  4. This earthquake M 1.8 about 15 lb of TNT

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.

For this area

No earthquake of M4 or more has been recorded within 50 km since our catalogue begins in 2016.

Before 2016, the USGS record lists 5 earthquakes of M5 or more within 50 km:

  1. 6.2 30 km SSW of Fort Greely, Alaska · 25 km W of this epicentre
  2. 5.7 31 km NNE of Paxson, Alaska · 42 km S of this epicentre
  3. 5.4 36 km NE of Paxson, Alaska · 46 km SSE of this epicentre
  4. 5.2 32 km SW of Dry Creek, Alaska · 36 km SSE of this epicentre
  5. 5.2 25 km NNE of Paxson, Alaska · 47 km S of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 63.7212, -145.3018. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Southeast Fairbanks Census Area, AK 104 km (64 mi) E earthquakes near Southeast Fairbanks Census Area
Fairbanks North Star Borough, AK 120 km (75 mi) NNW earthquakes near Fairbanks North Star Borough

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

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

  1. 1.5 30 km NNE of Paxson, Alaska
  2. 1.7 27 km NNE of Paxson, Alaska
  3. 1.9 30 km NE of Paxson, Alaska
  4. 2.2 28 km NNE of Paxson, Alaska
  5. 1.6 29 km NNE of Paxson, Alaska
  6. 1.7 28 km NNE of Paxson, Alaska
  7. 2.0 29 km NNE of Paxson, Alaska
  8. 1.7 Central Alaska
  9. 2.6 28 km NNE of Paxson, Alaska
  10. 2.5 29 km NNE of Paxson, Alaska
  11. 2.0 28 km NNE of Paxson, Alaska
  12. 1.5 31 km NE of Paxson, Alaska
  13. 1.9 26 km S of Fort Greely, Alaska
  14. 1.5 29 km SSW of Dry Creek, Alaska
  15. 2.1 Central Alaska

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

On USGS

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