Reviewed by USGSIndonesia104y ago
M6.3 earthquake 77 km WSW of Waingapu, Indonesia
Monday, October 15, 1923, 07:32:09 UTC · 9.941°S, 119.620°E
A magnitude 6.3 earthquake struck 77 km WSW of Waingapu, Indonesia on Monday, October 15, 1923, 07:32:09 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.0 on May 9, 1922.
- 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 earthquakeDashed circle: 100 km aftershock search area
In context
How big was it, and why here?
Energy released
49 kilotons of TNT
That is about 3 times the Hiroshima bomb. It released about 102 times the energy of a magnitude 5.0.
Tectonic setting
137 km
from the nearest mapped plate boundary, between the Sunda and Timor plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
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 lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.3 on October 15, 1923. 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 1 M5.0+ earthquake within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 3 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1836M7.5
Flores Sea
28 Nov 1836 · 209 km away
Limited damage (under $1M)tsunami
- 1837
Sumbawa Island: Bima
28 Nov 1837 · 202 km away · intensity IX
Limited damage (under $1M)
- 1836
Flores Sea
5 Mar 1836 · 209 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.