Reviewed by USGSIndonesia57y ago
M7.5 earthquake 209 km WSW of Sinabang, Indonesia
Friday, November 21, 1969, 02:05:37 UTC · 2.040°N, 94.545°E
A magnitude 7.5 earthquake struck 209 km WSW of Sinabang, Indonesia on Friday, November 21, 1969, 02:05:37 UTC, at a depth of 21.0 km (shallow). It is the strongest earthquake within 300 km since an M8.2 on January 4, 1907.
- Magnitude
- 7.5
- Major · mw
- Depth
- 21 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- V
- Moderate (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
3.1 megatons of TNT
That is about 204 times the Hiroshima bomb. It released about 6,457 times the energy of a magnitude 5.0.
Tectonic setting
31 km
from the nearest mapped plate boundary, between the Indian and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
21 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 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 32 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.2The 1907 Sumatra Earthquake and TsunamiJanuary 4, 1907 · 131 km NE of this epicenter
- 6.928 km NNE of Sinabang, IndonesiaNovember 4, 1917 · 231 km E of this epicenter
- 6.860 km W of Sinabang, IndonesiaNovember 2, 1908 · 155 km E of this epicenter
- 6.7171 km W of Meulaboh, IndonesiaDecember 9, 1929 · 233 km N of this epicenter
- 6.570 km SW of Meulaboh, IndonesiaAugust 21, 1967 · 222 km NE of this epicenter
- 6.384 km NW of Sinabang, IndonesiaJuly 1, 1937 · 195 km NE of this epicenter
- 6.375 km SSE of Sinabang, IndonesiaApril 2, 1956 · 237 km E of this epicenter
- 6.266 km WNW of Meulaboh, IndonesiaJuly 22, 1945 · 286 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 2 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2,188 recorded deaths. The most severe:
- 1907M8.2
Nw Sumatra: Gunungsitoli, Barus
4 Jan 1907 · 131 km away
2,188 deathsSevere damage ($5–24M)tsunami
- 1969M7.7
Off Nw Coast Sumatera
21 Nov 1969 · 9 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.