Reviewed by USGSTimor Leste43y ago
M5.6 earthquake 206 km NE of Lospalos, Timor Leste
Monday, December 26, 1983, 04:37:04 UTC · 7.366°S, 128.470°E
A magnitude 5.6 earthquake struck 206 km NE of Lospalos, Timor Leste on Monday, December 26, 1983, 04:37:04 UTC, at a depth of 144.7 km (intermediate). It is the strongest earthquake within 300 km since an M6.4 on December 12, 1983.
- Magnitude
- 5.6
- Moderate · mb
- Depth
- 145 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: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
4 kilotons of TNT
That is about 1/4 of the Hiroshima bomb. It released about 8 times the energy of a magnitude 5.0.
Tectonic setting
65 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
145 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 75 km
USGS lists 4 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M5.1 on January 8, 1984. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 398 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 · 133 km E of this epicenter
- 7.7Banda SeaNovember 2, 1950 · 99 km NE of this epicenter
- 7.5273 km WSW of Tual, IndonesiaJune 3, 1927 · 240 km E of this epicenter
- 7.3145 km NNE of Lospalos, Timor LesteAugust 30, 1917 · 93 km W of this epicenter
- 7.3172 km NE of Lospalos, Timor LesteNovember 24, 1983 · 36 km W of this epicenter
- 7.2187 km N of Baukau, Timor LesteFebruary 11, 1969 · 218 km W of this epicenter
- 7.258 km ENE of Lospalos, Timor LesteSeptember 29, 1905 · 150 km SW of this epicenter
- 7.1196 km SSE of Ambon, IndonesiaJuly 4, 1914 · 253 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 8 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 67 recorded deaths. The most severe:
- 1852M8.3
Maluku: Bandanaira
25 Nov 1852 · 275 km away · intensity IX
60 deathsSevere damage ($5–24M)tsunami
- 1763
Bandaneira
12 Sep 1763 · 227 km away · intensity X
7 deathsModerate damage ($1–5M)tsunami
- 1963M8.3
Banda Sea
4 Nov 1963 · 135 km away
Limited damage (under $1M)
- 1908M6.6
Timor
23 Mar 1908 · 299 km away
Limited damage (under $1M)tsunami
- 1918M8.1
Banda Sea
18 Nov 1918 · 71 km away
- 1950M8.1
Banda Sea
2 Nov 1950 · 149 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.