Reviewed by USGSIndonesia21y ago
M4.2 earthquake 143 km W of Banda Aceh, Indonesia
Friday, October 7, 2005, 06:14:57 UTC · 5.376°N, 94.052°E
A magnitude 4.2 earthquake struck 143 km W of Banda Aceh, Indonesia on Friday, October 7, 2005, 06:14:57 UTC, at a depth of 30.0 km (shallow).
- Magnitude
- 4.2
- Light · mb
- Depth
- 30 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: 50 km aftershock search area
In context
How big was it, and why here?
Energy released
30 tons of TNT
That is about 1/500 of the Hiroshima bomb. A magnitude 5.0 releases about 16 times more energy.
Tectonic setting
139 km
from the nearest mapped plate boundary, between the Sunda and Burma plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
30 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 50 km
USGS lists 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.7 on November 3, 2005. 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 553 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.2284 km WNW of Sabang, IndonesiaDecember 26, 2004 · 209 km NW of this epicenter
- 7.0190 km WNW of Sabang, IndonesiaMay 17, 1955 · 163 km N of this epicenter
- 7.040 km NE of Meulaboh, IndonesiaAugust 3, 1935 · 283 km SE of this epicenter
- 6.975 km WSW of Banda Aceh, IndonesiaAugust 23, 1936 · 74 km E of this epicenter
- 6.95 km W of Banda Aceh, IndonesiaApril 2, 1964 · 137 km E of this epicenter
- 6.968 km WSW of Sabang, IndonesiaApril 4, 1983 · 84 km NE of this epicenter
- 6.8238 km WNW of Sabang, IndonesiaJanuary 20, 1917 · 194 km N of this epicenter
- 6.7171 km W of Meulaboh, IndonesiaDecember 9, 1929 · 150 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 18 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 9 recorded deaths. The most severe:
- 1936M7.3
Banda Aceh,Lhok Sukon,Lhoksemawe
23 Aug 1936 · 108 km away · intensity VIII
9 deathsModerate damage ($1–5M)tsunami
- 1964M7.0
Banda Aceh
2 Apr 1964 · 191 km away · intensity VII
Severe damage ($5–24M)tsunami
- 1837M7.3
Banda Atjeh
29 Sep 1837 · 216 km away
Moderate damage ($1–5M)tsunami
- 1983M6.6
Sumatera: Banda Aceh
4 Apr 1983 · 84 km away · intensity VII
$1 million damage
- 1982M6.3
Little Nicobar Island
20 Jan 1982 · 175 km away · intensity VIII
Moderate damage ($1–5M)
- 1997M6.0
N. Sumatera, Aceh, Banda Aceh, Medan
20 Aug 1997 · 293 km away
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.