Reviewed by USGSIndonesia21y ago
M4.1 earthquake 55 km S of Sinabang, Indonesia
Tuesday, September 27, 2005, 21:00:35 UTC · 1.983°N, 96.448°E
A magnitude 4.1 earthquake struck 55 km S of Sinabang, Indonesia on Tuesday, September 27, 2005, 21:00:35 UTC, at a depth of 30.0 km (shallow).
- Magnitude
- 4.1
- 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
21 tons of TNT
That is about 1/707 of the Hiroshima bomb. A magnitude 5.0 releases about 22 times more energy.
Tectonic setting
35 km
from the nearest mapped plate boundary, between the Sunda and Burma plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
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 6 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.8 on October 7, 2005. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.662 km SSE of Sinabang, Indonesia21y ago · 23 km E of this epicenter
- 4.238 km SW of Sinabang, Indonesia21y ago · 46 km NW of this epicenter
- 4.629 km SW of Sinabang, Indonesia21y ago · 45 km NW of this epicenter
- 4.673 km SE of Sinabang, Indonesia21y ago · 38 km E of this epicenter
- 4.821 km SW of Sinabang, Indonesia21y ago · 48 km NW of this epicenter
- 4.529 km S of Sinabang, Indonesia21y ago · 26 km N of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 442 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 9.12004 Sumatra - Andaman Islands EarthquakeDecember 26, 2004 · 155 km N of this epicenter
- 8.678 km WSW of Singkil, IndonesiaMarch 28, 2005 · 74 km E of this epicenter
- 8.2The 1907 Sumatra Earthquake and TsunamiJanuary 4, 1907 · 128 km NW of this epicenter
- 7.5209 km WSW of Sinabang, IndonesiaNovember 21, 1969 · 212 km W of this epicenter
- 7.450 km NW of Sinabang, IndonesiaNovember 2, 2002 · 102 km NW of this epicenter
- 7.1190 km SSW of Sibolga, IndonesiaNovember 17, 1984 · 265 km SE of this epicenter
- 7.186 km WSW of Pangkalan Brandan, IndonesiaSeptember 19, 1936 · 227 km NE of this epicenter
- 7.040 km NE of Meulaboh, IndonesiaAugust 3, 1935 · 267 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 17 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 232,379 recorded deaths. The most severe:
- 2004M9.1
Sumatra: Aceh: Off West Coast
26 Dec 2004 · 155 km away
227,899 deaths$10 billion damagetsunami
- 1907M8.2
Nw Sumatra: Gunungsitoli, Barus
4 Jan 1907 · 128 km away
2,188 deathsSevere damage ($5–24M)tsunami
- 2005M8.6
Sumatera: Sw
28 Mar 2005 · 74 km away
1,319 deaths$37 million damagetsunami
- 1861M7.0
Sw. Sumatra
9 Mar 1861 · 279 km away
950 deathsSevere damage ($5–24M)tsunami
- 1936
N Sumatera: Tapanuli, Karo
9 Sep 1936 · 205 km away · intensity VIII
17 deathsModerate damage ($1–5M)
- 2002M7.3
Sumatera: Simeulue
2 Nov 2002 · 102 km away
3 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.