24 km NNE of Waialua, Hawaii

2017-08-23 20:11 UTC · 13 km deep · released about 2.8 tons of TNT

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: 2017-08-23 20:11 UTC
Magnitude: M 3.5 (ml)
Depth: 13 km below the surface
Felt: 1 report · strongest reported intensity II
Measured shaking: intensity I (ShakeMap)
Nearest: Kalawao County, 35 km WSW
Status: Reviewed by a seismologist

USGS · last changed by USGS 1513 days ago · we first saw it 1513 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage. 1 person has reported feeling it to USGS.

How big was it?

This earthquake released about 2.8 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.5 would have released about 32 times as much.

Northridge, California 1994 M 6.7 61,000× the energy of this one
Mineral, Virginia 2011 M 5.8 2,700× the energy of this one
Magna, Utah 2020 M 5.7 1,900× the energy of this one
This earthquake M 3.5 about 2.8 tons of TNT
Around the size people start to feel M 3.0 this one released 5.8× 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

Map loads when it scrolls into view

Epicentre 21.2917, -156.6488. Map © OpenStreetMap contributors.

Nearby places

Place	Distance	Direction
Kalawao County, HI	35 km (22 mi)	ENE of here	earthquakes near Kalawao County
Maui County, HI	49 km (30 mi)	N of here	earthquakes near Maui County

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

Aftershocks so far

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

2.4 6 km NNW of Haiku-Pauwela, Hawaii 23:24 UTC
2.5 41 km N of Haiku-Pauwela, Hawaii 09:52 UTC
3.0 28 km NNE of Waihee-Waiehu, Hawaii 10:15 UTC
2.8 25 km NE of Kualapu‘u, Hawaii 12:12 UTC
3.0 26 km NNE of Waialua, Hawaii 00:21 UTC
3.4 15 km NE of Waialua, Hawaii 13:16 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 11:15 UTC. QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

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.