33 km WNW of H?w?, Hawaii

2017-07-30 12:01 UTC · 16 km deep · released about 31 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: 2017-07-30 12:01 UTC
Magnitude: M 4.2 (ml)
Depth: 16 km below the surface
Felt: 217 reports · strongest reported intensity IV
Measured shaking: intensity III (ShakeMap)
USGS impact alert: green
Nearest: Maui County, 72 km NW
Status: Reviewed by a seismologist

USGS · last changed by USGS 2275 days ago · we first saw it 2275 days ago

This was a light earthquake. It is usually felt clearly nearby and can rattle windows and dishes, but damage is uncommon. 217 people have reported feeling it to USGS.

How big was it?

This earthquake released about 31 tons of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 5.2 would have released about 32 times as much.

Northridge, California 1994 M 6.7 5,400× the energy of this one
Mineral, Virginia 2011 M 5.8 240× the energy of this one
Magna, Utah 2020 M 5.7 170× the energy of this one
This earthquake M 4.2 about 31 tons of TNT
Around the size people start to feel M 3.0 this one released 65× 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 20.4045, -156.1020. Map © OpenStreetMap contributors.

Nearby places

Place	Distance	Direction
Maui County, HI	72 km (45 mi)	SE of here	earthquakes near Maui County
Hawaii County, HI	109 km (68 mi)	NW of here	earthquakes near Hawaii County
Kalawao County, HI	128 km (80 mi)	SE of here	earthquakes near Kalawao County

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

Aftershocks so far

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

2.3 24 km SSE of Hana, Hawaii 21:54 UTC
2.4 9 km S of Kapaau, Hawaii 11:45 UTC
2.3 33 km WSW of H?w?, Hawaii 10:55 UTC
1.9 5 km SSE of Kapaau, Hawaii 10:29 UTC
4.0 10 km S of Kapaau, Hawaii 10:05 UTC
3.1 10 km N of Puako, Hawaii 03:42 UTC
3.1 15 km NW of Puako, Hawaii 21:36 UTC
1.7 2 km SSW of H?w?, Hawaii 01:50 UTC
2.8 39 km SSE of M?kena, Hawaii 10:58 UTC
2.8 9 km WNW of H?w?, Hawaii 22:49 UTC
2.7 6 km E of K?hei, Hawaii 13:34 UTC
2.4 13 km W of H?w?, Hawaii 21:40 UTC
2.1 2 km SE of Kapaau, Hawaii 17:02 UTC
2.4 22 km NW of Puako, Hawaii 02:10 UTC
2.3 11 km NNE of Hala‘ula, Hawaii 00:34 UTC

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of 08:24 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 4.7 on 2017-02-17 — it released about 4.7 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.