Reviewed by USGSIndonesia61y ago
M6.7 earthquake 53 km W of Luwuk, Indonesia
Saturday, April 23, 1966, 00:09:33 UTC · 0.964°S, 122.308°E
A magnitude 6.7 earthquake struck 53 km W of Luwuk, Indonesia on Saturday, April 23, 1966, 00:09:33 UTC, at a depth of 22.0 km (shallow). It is the strongest earthquake within 300 km since an M6.7 on June 30, 1964.
- Magnitude
- 6.7
- Strong · mw
- Depth
- 22 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 earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
142 kilotons of TNT
That is about 9 times the Hiroshima bomb. It released about 299 times the energy of a magnitude 5.0.
Tectonic setting
146 km
from the nearest mapped plate boundary, between the Molucca Sea and Banda Sea plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
22 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 M6.1 on April 23, 1966. 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 72 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.11939 Sulawesi EarthquakeDecember 21, 1939 · 118 km NE of this epicenter
- 7.8160 km W of Gorontalo, IndonesiaJanuary 22, 1905 · 191 km NW of this epicenter
- 7.7120 km NE of Palu, IndonesiaMay 19, 1938 · 222 km NW of this epicenter
- 7.433 km NW of Gorontalo, IndonesiaNovember 8, 1941 · 197 km N of this epicenter
- 7.1156 km NW of Gorontalo, IndonesiaJanuary 11, 1913 · 263 km N of this epicenter
- 6.8161 km S of Luwuk, IndonesiaNovember 19, 1913 · 160 km S of this epicenter
- 6.8109 km WSW of Luwuk, IndonesiaMarch 17, 1909 · 59 km SW of this epicenter
- 6.747 km WNW of Luwuk, IndonesiaJune 30, 1964 · 26 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 67 recorded deaths. The most severe:
- 1927M6.2
Sulawesi: Donggala
1 Dec 1927 · 173 km away · intensity VII
50 deathsSevere damage ($5–24M)tsunami
- 1938M7.7
Sulawesi Island
19 May 1938 · 222 km away · intensity IX
17 deathsSevere damage ($5–24M)tsunami
- 1939M8.0
Centrtal Sulawesi: Kalo,Luwuk,Sula I
21 Dec 1939 · 132 km away
Moderate damage ($1–5M)tsunami
- 1907
Sulawesi: Lemo, Colo, Anja, Olu Congko
30 Jul 1907 · 185 km away · intensity VIII
Moderate damage ($1–5M)
- 1960
Central Sulawesi: Una-Una Island
29 Apr 1960 · 104 km away · intensity VIII
Moderate damage ($1–5M)
- 1905M8.4
Minahassa Peninsula
22 Jan 1905 · 232 km away
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.