Reviewed by USGSIndonesia107y ago
M6.5 earthquake 271 km S of Pagar Alam, Indonesia
Thursday, March 3, 1921, 08:20:17 UTC · 6.464°S, 102.994°E
A magnitude 6.5 earthquake struck 271 km S of Pagar Alam, Indonesia on Thursday, March 3, 1921, 08:20:17 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M6.5 on October 12, 1919.
- Magnitude
- 6.5
- Strong · mw
- Depth
- 15 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 earthquake
In context
How big was it, and why here?
Energy released
82 kilotons of TNT
That is about 5 times the Hiroshima bomb. It released about 172 times the energy of a magnitude 5.0.
Tectonic setting
99 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
15 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 100 km
USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 10 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.769 km SSE of Bengkulu, IndonesiaApril 15, 1916 · 240 km N of this epicenter
- 6.679 km WSW of Labuan, IndonesiaAugust 13, 1913 · 247 km E of this epicenter
- 6.5104 km WSW of Bengkulu, IndonesiaOctober 12, 1919 · 295 km NW of this epicenter
- 6.4200 km SW of Bandar Lampung, IndonesiaOctober 4, 1907 · 120 km E of this epicenter
- 6.3174 km SSW of Pagar Alam, IndonesiaFebruary 13, 1918 · 101 km N of this epicenter
- 6.385 km SSW of Kotabumi, IndonesiaApril 2, 1919 · 197 km NE of this epicenter
- 6.3159 km SSW of Pagar Alam, IndonesiaJuly 14, 1914 · 137 km N of this epicenter
- 6.3129 km SW of Bengkulu, IndonesiaJanuary 18, 1919 · 264 km NW 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. The most severe:
- 1770M7.0
Sumatra:
1770 · 196 km away
Severe damage ($5–24M)tsunami
- 1852M6.5
Java: Djakarta; Sumatra: Telukbetung
9 Jan 1852 · 277 km away · intensity VIII
Limited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.