Reviewed by USGSTimor Leste39y ago
M4.7 earthquake 257 km ENE of Lospalos, Timor Leste
Monday, August 3, 1987, 16:39:20 UTC · 7.250°S, 128.952°E
A magnitude 4.7 earthquake struck 257 km ENE of Lospalos, Timor Leste on Monday, August 3, 1987, 16:39:20 UTC, at a depth of 143.6 km (intermediate). It is the strongest earthquake within 300 km since an M4.8 on August 3, 1987.
- Magnitude
- 4.7
- Light · mb
- Depth
- 144 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
169 tons of TNT
That is about 1/89 of the Hiroshima bomb. A magnitude 5.0 releases about 3 times more energy.
Tectonic setting
77 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
144 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 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M5.0 on August 7, 1987. 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 568 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 · 79 km NE of this epicenter
- 7.7Banda SeaNovember 2, 1950 · 54 km NE of this epicenter
- 7.5273 km WSW of Tual, IndonesiaJune 3, 1927 · 186 km E of this epicenter
- 7.3145 km NNE of Lospalos, Timor LesteAugust 30, 1917 · 147 km W of this epicenter
- 7.3172 km NE of Lospalos, Timor LesteNovember 24, 1983 · 90 km W of this epicenter
- 7.2187 km N of Baukau, Timor LesteFebruary 11, 1969 · 267 km W of this epicenter
- 7.258 km ENE of Lospalos, Timor LesteSeptember 29, 1905 · 200 km SW of this epicenter
- 7.1196 km SSE of Ambon, IndonesiaJuly 4, 1914 · 230 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 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 · 239 km away · intensity IX
60 deathsSevere damage ($5–24M)tsunami
- 1763
Bandaneira
12 Sep 1763 · 181 km away · intensity X
7 deathsModerate damage ($1–5M)tsunami
- 1975M5.9
Maluku: Bandanaira
15 Jan 1975 · 276 km away · intensity VII
Moderate damage ($1–5M)tsunami
- 1963M8.3
Banda Sea
4 Nov 1963 · 82 km away
Limited damage (under $1M)
- 1918M8.1
Banda Sea
18 Nov 1918 · 28 km away
- 1950M8.1
Banda Sea
2 Nov 1950 · 103 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.