M4.2 earthquake 186 km ENE of Lospalos, Timor Leste

Monday, December 25, 2023, 05:44:10 UTC · 7.660°S, 128.456°E

A magnitude 4.2 earthquake struck 186 km ENE of Lospalos, Timor Leste on Monday, December 25, 2023, 05:44:10 UTC, at a depth of 158.9 km (intermediate).

Magnitude: 4.2; Light · mb
Depth: 159 km; Intermediate
Felt reports: 0; Did You Feel It?
Est. shaking: —; No ShakeMap
PAGER alert: None; Not issued
Tsunami: No flag; USGS feed

Outlined circle: this earthquakeDashed circle: 50 km aftershock search area

In context

How big was it, and why here?

Energy released

30 tons of TNT

That is about 1/500 of the Hiroshima bomb. A magnitude 5.0 releases about 16 times more energy.

Tectonic setting

95 km

from the nearest mapped plate boundary, between the Banda Sea and Timor plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: intermediate

159 km

Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.

Did You Feel It?

Where it was felt

No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.

I felt it — report to USGS ↗

USGS PAGER estimate

Who was exposed to shaking

USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.

After the main event

Aftershocks within 50 km

USGS lists 7 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.9 on January 5, 2024. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 1,330 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 8 recorded deaths. The most severe:

1763
Bandaneira
12 Sep 1763 · 251 km away · intensity X
7 deathsModerate damage ($1–5M)tsunami
2023M7.6
Banda Sea
9 Jan 2023 · 187 km away · intensity V
1 deathModerate damage ($1–5M)tsunami
1963M8.3
Banda Sea
4 Nov 1963 · 153 km away
Limited damage (under $1M)
1908M6.6
Timor
23 Mar 1908 · 267 km away
Limited damage (under $1M)tsunami
1918M8.1
Banda Sea
18 Nov 1918 · 95 km away
1950M8.1
Banda Sea
2 Nov 1950 · 173 km away

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers