Reviewed by USGSTimor Leste105y ago
M6.6 earthquake 99 km NNW of Pante Makasar, Timor Leste
Wednesday, March 28, 1923, 04:28:30 UTC · 8.376°S, 124.019°E
A magnitude 6.6 earthquake struck 99 km NNW of Pante Makasar, Timor Leste on Wednesday, March 28, 1923, 04:28:30 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M7.0 on August 6, 1914.
- Magnitude
- 6.6
- Strong · mw
- Depth
- 35 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
In context
How big was it, and why here?
Energy released
108 kilotons of TNT
That is about 7 times the Hiroshima bomb. It released about 226 times the energy of a magnitude 5.0.
Tectonic setting
66 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: shallow
35 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
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 100 km
USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 5 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.0194 km SE of Baubau, IndonesiaAugust 6, 1914 · 203 km N of this epicenter
- 6.811 km WSW of Ainaro, Timor LesteMarch 23, 1908 · 171 km SE of this epicenter
- 6.5201 km SSE of Baubau, IndonesiaAugust 18, 1912 · 158 km NW of this epicenter
- 6.571 km NW of Naisano Dua, IndonesiaOctober 16, 1918 · 106 km SW of this epicenter
- 6.3Banda SeaMay 19, 1920 · 255 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 3 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 250 recorded deaths. The most severe:
- 1896
Timor: Alor Island
18 Apr 1896 · 82 km away · intensity VIII
250 deathsModerate damage ($1–5M)
- 1814
Timor Island, Kupang, Kissar Island
1814 · 209 km away
Severe damage ($5–24M)tsunami
- 1891M7.0
Timor Sea
5 Oct 1891 · 69 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.