Reviewed by USGSTimor Leste3y ago
M4.9 earthquake 171 km NE of Lospalos, Timor Leste
Tuesday, August 1, 2023, 12:13:39 UTC · 7.482°S, 128.156°E
A magnitude 4.9 earthquake struck 171 km NE of Lospalos, Timor Leste on Tuesday, August 1, 2023, 12:13:39 UTC, at a depth of 150.1 km (intermediate). It is the strongest earthquake within 300 km since an M5.3 on July 6, 2023.
- Magnitude
- 4.9
- Light · mb
- Depth
- 150 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
338 tons of TNT
That is about 1/45 of the Hiroshima bomb. A magnitude 5.0 releases about 1 times more energy.
Tectonic setting
63 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
150 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 5 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.6 on August 11, 2023. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.4142 km NE of Lospalos, Timor Leste3y ago · 34 km W of this epicenter
- 4.0153 km NE of Lospalos, Timor Leste3y ago · 41 km W of this epicenter
- 4.4166 km NE of Lospalos, Timor Leste3y ago · 17 km NW of this epicenter
- 4.6182 km NE of Lospalos, Timor Leste3y ago · 12 km E of this epicenter
- 4.4171 km NE of Lospalos, Timor Leste3y ago · 32 km NW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 1,293 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.11963 Banda Sea EarthquakeNovember 4, 1963 · 170 km E of this epicenter
- 7.7Banda SeaNovember 2, 1950 · 135 km NE of this epicenter
- 7.6Pulau Pulau Tanimbar, IndonesiaJanuary 9, 2023 · 210 km E of this epicenter
- 7.6196 km S of Ambon, IndonesiaJanuary 27, 2006 · 223 km N of this epicenter
- 7.5273 km WSW of Tual, IndonesiaJune 3, 1927 · 277 km E of this epicenter
- 7.3145 km NNE of Lospalos, Timor LesteAugust 30, 1917 · 60 km W of this epicenter
- 7.3125 km NNE of Lospalos, Timor LesteDecember 29, 2021 · 64 km W of this epicenter
- 7.3281 km WSW of Tual, IndonesiaDecember 20, 1992 · 266 km E of this epicenter
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 · 262 km away · intensity X
7 deathsModerate damage ($1–5M)tsunami
- 2023M7.6
Banda Sea
9 Jan 2023 · 213 km away · intensity V
1 deathModerate damage ($1–5M)tsunami
- 1963M8.3
Banda Sea
4 Nov 1963 · 172 km away
Limited damage (under $1M)
- 1908M6.6
Timor
23 Mar 1908 · 295 km away
Limited damage (under $1M)tsunami
- 1918M8.1
Banda Sea
18 Nov 1918 · 107 km away
- 1950M8.1
Banda Sea
2 Nov 1950 · 184 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.