Reviewed by USGSIndonesia43y ago
M5.1 earthquake in Kepulauan Babar, Indonesia
Tuesday, January 31, 1984, 03:23:32 UTC · 7.015°S, 129.509°E
A magnitude 5.1 earthquake struck in Kepulauan Babar, Indonesia on Tuesday, January 31, 1984, 03:23:32 UTC, at a depth of 136.3 km (intermediate). It is the strongest earthquake within 300 km since an M5.3 on January 20, 1984.
- Magnitude
- 5.1
- Moderate · mb
- Depth
- 136 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
674 tons of TNT
That is about 1/22 of the Hiroshima bomb. It released about 1 times the energy of a magnitude 5.0.
Tectonic setting
62 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
136 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 3 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M4.6 on February 1, 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 461 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 · 12 km NE of this epicenter
- 7.7Banda SeaNovember 2, 1950 · 42 km NW of this epicenter
- 7.5273 km WSW of Tual, IndonesiaJune 3, 1927 · 119 km E of this epicenter
- 7.3145 km NNE of Lospalos, Timor LesteAugust 30, 1917 · 211 km W of this epicenter
- 7.3172 km NE of Lospalos, Timor LesteNovember 24, 1983 · 157 km W of this epicenter
- 7.258 km ENE of Lospalos, Timor LesteSeptember 29, 1905 · 265 km SW of this epicenter
- 7.1196 km SSE of Ambon, IndonesiaJuly 4, 1914 · 207 km N of this epicenter
- 7.1186 km NE of Lospalos, Timor LesteMay 15, 1962 · 147 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 15 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 · 198 km away · intensity IX
60 deathsSevere damage ($5–24M)tsunami
- 1763
Bandaneira
12 Sep 1763 · 125 km away · intensity X
7 deathsModerate damage ($1–5M)tsunami
- 1710
Bandaneira
6 Mar 1710 · 280 km away · intensity IX
Severe damage ($5–24M)tsunami
- 1975M5.9
Maluku: Bandanaira
15 Jan 1975 · 231 km away · intensity VII
Moderate damage ($1–5M)tsunami
- 1890
Bandaneira
23 Nov 1890 · 283 km away · intensity VII
Moderate damage ($1–5M)
- 1963M8.3
Banda Sea
4 Nov 1963 · 19 km away
Limited damage (under $1M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.