Reviewed by USGSIndonesia21y ago
M4.7 earthquake 23 km SW of Sinabang, Indonesia
Friday, October 28, 2005, 17:23:29 UTC · 2.358°N, 96.209°E
A magnitude 4.7 earthquake struck 23 km SW of Sinabang, Indonesia on Friday, October 28, 2005, 17:23:29 UTC, at a depth of 30.0 km (shallow). It is the strongest earthquake within 300 km since an M4.7 on October 28, 2005.
- Magnitude
- 4.7
- Light · mwc
- 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
169 tons of TNT
That is about 1/89 of the Hiroshima bomb. A magnitude 5.0 releases about 3 times more energy.
Tectonic setting
61 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 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.7 on October 31, 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 449 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 · 107 km N of this epicenter
- 8.678 km WSW of Singkil, IndonesiaMarch 28, 2005 · 104 km E of this epicenter
- 8.2The 1907 Sumatra Earthquake and TsunamiJanuary 4, 1907 · 84 km NW of this epicenter
- 7.5209 km WSW of Sinabang, IndonesiaNovember 21, 1969 · 188 km W of this epicenter
- 7.450 km NW of Sinabang, IndonesiaNovember 2, 2002 · 54 km N of this epicenter
- 7.186 km WSW of Pangkalan Brandan, IndonesiaSeptember 19, 1936 · 212 km NE of this epicenter
- 7.040 km NE of Meulaboh, IndonesiaAugust 3, 1935 · 226 km N of this epicenter
- 7.085 km SSE of Meulaboh, IndonesiaJune 20, 1976 · 116 km N of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 16 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 231,429 recorded deaths. The most severe:
- 2004M9.1
Sumatra: Aceh: Off West Coast
26 Dec 2004 · 107 km away
227,899 deaths$10 billion damagetsunami
- 1907M8.2
Nw Sumatra: Gunungsitoli, Barus
4 Jan 1907 · 84 km away
2,188 deathsSevere damage ($5–24M)tsunami
- 2005M8.6
Sumatera: Sw
28 Mar 2005 · 104 km away
1,319 deaths$37 million damagetsunami
- 1936
N Sumatera: Tapanuli, Karo
9 Sep 1936 · 192 km away · intensity VIII
17 deathsModerate damage ($1–5M)
- 2002M7.3
Sumatera: Simeulue
2 Nov 2002 · 54 km away
3 deathsSevere damage ($5–24M)
- 1987M6.6
Sumatera: N, Tarutung-Lake Toba,
25 Apr 1987 · 295 km away
2 deaths$1 million damage
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.