Reviewed by USGSIndonesia49y ago
M5.5 earthquake 204 km SSW of Waingapu, Indonesia
Friday, October 7, 1977, 14:38:36 UTC · 11.265°S, 119.346°E
A magnitude 5.5 earthquake struck 204 km SSW of Waingapu, Indonesia on Friday, October 7, 1977, 14:38:36 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M6.3 on October 7, 1977.
- Magnitude
- 5.5
- Moderate · mb
- Depth
- 33 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 earthquakeDashed circle: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
3 kilotons of TNT
That is about 1/6 of the Hiroshima bomb. It released about 6 times the energy of a magnitude 5.0.
Tectonic setting
15 km
from the nearest mapped plate boundary, between the Sunda and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
33 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 75 km
USGS lists 4 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M5.6 on October 12, 1977. 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 163 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.31977 Sumba, Indonesia EarthquakeAugust 19, 1977 · 106 km W of this epicenter
- 7.084 km SSE of Dompu, IndonesiaMay 9, 1922 · 233 km N of this epicenter
- 6.835 km SW of Ruteng, IndonesiaJanuary 26, 1968 · 285 km N of this epicenter
- 6.4248 km S of Taliwang, IndonesiaMay 28, 1972 · 263 km W of this epicenter
- 6.377 km WSW of Waingapu, IndonesiaOctober 15, 1923 · 150 km N of this epicenter
- 6.362 km S of Waingapu, IndonesiaOctober 15, 1923 · 153 km NE of this epicenter
- 6.3161 km S of Sumbawa Besar, IndonesiaOctober 7, 1977 · 265 km NW of this epicenter
- 6.3139 km SSE of Dompu, IndonesiaDecember 21, 1938 · 178 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 189 recorded deaths. The most severe:
- 1977M8.3
Sunda Islands
19 Aug 1977 · 106 km away
189 deaths$1 million damagetsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.