Reviewed by USGSIndonesia105y ago
M6.4 earthquake 54 km NE of Luwuk, Indonesia
Friday, February 23, 1923, 05:51:59 UTC · 0.630°S, 123.161°E
A magnitude 6.4 earthquake struck 54 km NE of Luwuk, Indonesia on Friday, February 23, 1923, 05:51:59 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M6.4 on September 11, 1922.
- Magnitude
- 6.4
- Strong · mw
- Depth
- 35 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VI
- Strong (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
67 kilotons of TNT
That is about 4 times the Hiroshima bomb. It released about 140 times the energy of a magnitude 5.0.
Tectonic setting
150 km
from the nearest mapped plate boundary, between the Molucca Sea and Sunda plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
35 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 8 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8160 km W of Gorontalo, IndonesiaJanuary 22, 1905 · 220 km NW of this epicenter
- 7.3108 km SE of Tondano, IndonesiaMay 5, 1908 · 288 km NE of this epicenter
- 7.1156 km NW of Gorontalo, IndonesiaJanuary 11, 1913 · 262 km NW of this epicenter
- 6.8161 km S of Luwuk, IndonesiaNovember 19, 1913 · 209 km S of this epicenter
- 6.8109 km WSW of Luwuk, IndonesiaMarch 17, 1909 · 160 km SW of this epicenter
- 6.730 km N of Luwuk, IndonesiaDecember 23, 1912 · 47 km W of this epicenter
- 6.469 km NNE of Luwuk, IndonesiaSeptember 11, 1922 · 42 km NW of this epicenter
- 6.1119 km N of Kendari, IndonesiaJune 3, 1917 · 260 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 6 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1859M7.3
Sulawesi
29 Jul 1859 · 270 km away
Moderate damage ($1–5M)tsunami
- 1907
Sulawesi: Lemo, Colo, Anja, Olu Congko
30 Jul 1907 · 284 km away · intensity VIII
Moderate damage ($1–5M)
- 1905M8.4
Minahassa Peninsula
22 Jan 1905 · 182 km away
- 1859
Sulawesi: Manado, Belang
17 Dec 1859 · 258 km away
tsunami
- 1871
Gorontalo
25 Aug 1871 · 127 km away
tsunami
- 1920
N. Moluccas Islands
29 Jan 1920 · 169 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.