Reviewed by USGSIndonesia87y ago
M6.3 earthquake south of Java, Indonesia
Thursday, March 21, 1940, 13:52:54 UTC · 10.219°S, 107.711°E
A magnitude 6.3 earthquake struck south of Java, Indonesia on Thursday, March 21, 1940, 13:52:54 UTC, at a depth of 15.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.
- Magnitude
- 6.3
- 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
38 kilotons of TNT
That is about 3 times the Hiroshima bomb. It released about 80 times the energy of a magnitude 5.0.
Tectonic setting
22 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 7 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 6.2166 km SSW of Bambanglipuro, IndonesiaAugust 31, 1918 · 254 km E of this epicenter
- 6.083 km SSW of Banjar, IndonesiaApril 24, 1919 · 276 km N of this epicenter
- 6.0186 km S of Pundong, IndonesiaSeptember 11, 1926 · 296 km E of this epicenter
- 5.8248 km SSW of Pelabuhanratu, IndonesiaMarch 15, 1930 · 237 km NW of this epicenter
- 5.899 km SSE of Pelabuhanratu, IndonesiaJuly 13, 1933 · 281 km N of this epicenter
- 5.8103 km S of Banjar, IndonesiaSeptember 8, 1927 · 236 km N of this epicenter
- 5.6229 km SSW of Banjar, IndonesiaDecember 17, 1937 · 175 km NW 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 1 recorded deaths. The most severe:
- 1937M7.2
Java: Jogyakarta: Klumpit,Prambanan
27 Sep 1937 · 288 km away · intensity IX
1 deathSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.