Reviewed by USGSIndonesia18y ago
M4.7 earthquake 106 km SE of Sinabang, Indonesia
Thursday, July 31, 2008, 15:16:52 UTC · 1.749°N, 96.998°E
A magnitude 4.7 earthquake struck 106 km SE of Sinabang, Indonesia on Thursday, July 31, 2008, 15:16:52 UTC, at a depth of 21.1 km (shallow). It is the strongest earthquake within 300 km since an M4.9 on July 22, 2008.
- Magnitude
- 4.7
- Light · mb
- Depth
- 21 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
29 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
21 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 2 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.6 on August 20, 2008. 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 565 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 · 206 km NW of this epicenter
- 8.678 km WSW of Singkil, IndonesiaMarch 28, 2005 · 39 km N of this epicenter
- 8.2The 1907 Sumatra Earthquake and TsunamiJanuary 4, 1907 · 193 km NW of this epicenter
- 7.6212 km W of Pariaman, IndonesiaDecember 28, 1935 · 264 km SE of this epicenter
- 7.5209 km WSW of Sinabang, IndonesiaNovember 21, 1969 · 275 km W of this epicenter
- 7.450 km NW of Sinabang, IndonesiaNovember 2, 2002 · 157 km NW of this epicenter
- 7.456 km NW of Sinabang, IndonesiaFebruary 20, 2008 · 161 km NW of this epicenter
- 7.1190 km SSW of Sibolga, IndonesiaNovember 17, 1984 · 207 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 23 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 232,683 recorded deaths. The most severe:
- 2004M9.1
Sumatra: Aceh: Off West Coast
26 Dec 2004 · 206 km away
227,899 deaths$10 billion damagetsunami
- 1907M8.2
Nw Sumatra: Gunungsitoli, Barus
4 Jan 1907 · 193 km away
2,188 deathsSevere damage ($5–24M)tsunami
- 2005M8.6
Sumatera: Sw
28 Mar 2005 · 39 km away
1,319 deaths$37 million damagetsunami
- 1861M7.0
Sw. Sumatra
9 Mar 1861 · 223 km away
950 deathsSevere damage ($5–24M)tsunami
- 1797M8.0
Sw. Sumatra
10 Feb 1797 · 295 km away · intensity IX
300 deathsModerate damage ($1–5M)tsunami
- 1936
N Sumatera: Tapanuli, Karo
9 Sep 1936 · 203 km away · intensity VIII
17 deathsModerate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.