Reviewed by USGSIndonesia39y ago
M4.6 earthquake 219 km W of Tual, Indonesia
Sunday, June 21, 1987, 08:59:41 UTC · 5.703°S, 130.768°E
A magnitude 4.6 earthquake struck 219 km W of Tual, Indonesia on Sunday, June 21, 1987, 08:59:41 UTC, at a depth of 77.3 km (intermediate). It is the strongest earthquake within 300 km since an M5.7 on June 20, 1987.
- Magnitude
- 4.6
- Light · mb
- Depth
- 77 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
120 tons of TNT
That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.
Tectonic setting
110 km
from the nearest mapped plate boundary, between the Banda Sea and Timor plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
77 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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.1 on July 6, 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 529 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.51938 Banda Sea EarthquakeFebruary 1, 1938 · 119 km NE of this epicenter
- 8.11963 Banda Sea EarthquakeNovember 4, 1963 · 190 km SW of this epicenter
- 7.7Banda SeaNovember 2, 1950 · 215 km SW of this epicenter
- 7.5273 km WSW of Tual, IndonesiaJune 3, 1927 · 120 km S of this epicenter
- 7.1196 km SSE of Ambon, IndonesiaJuly 4, 1914 · 190 km W of this epicenter
- 7.1217 km W of Tual, IndonesiaJune 17, 1987 · 14 km N of this epicenter
- 7.0188 km SSE of Amahai, IndonesiaJune 9, 1920 · 155 km NW of this epicenter
- 6.9Banda SeaOctober 30, 1909 · 182 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 16 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 69 recorded deaths. The most severe:
- 1852M8.3
Maluku: Bandanaira
25 Nov 1852 · 123 km away · intensity IX
60 deathsSevere damage ($5–24M)tsunami
- 1763
Bandaneira
12 Sep 1763 · 91 km away · intensity X
7 deathsModerate damage ($1–5M)tsunami
- 1711M7.0
Banda Sea
5 Sep 1711 · 272 km away
2 deathsLimited damage (under $1M)tsunami
- 1710
Bandaneira
6 Mar 1710 · 162 km away · intensity IX
Severe damage ($5–24M)tsunami
- 1938M8.6
New Guinea
1 Feb 1938 · 119 km away · intensity VI
Moderate damage ($1–5M)tsunami
- 1975M5.9
Maluku: Bandanaira
15 Jan 1975 · 115 km away · intensity VII
Moderate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.