Reviewed by USGSIndonesia20y ago
M4.0 earthquake 271 km SSW of Kroya, Indonesia
Sunday, August 27, 2006, 18:32:43 UTC · 9.936°S, 108.404°E
A magnitude 4.0 earthquake struck 271 km SSW of Kroya, Indonesia on Sunday, August 27, 2006, 18:32:43 UTC, at a depth of 10.0 km (shallow).
- Magnitude
- 4.0
- Light · mb
- Depth
- 10 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
15 tons of TNT
That is about 1/998 of the Hiroshima bomb. A magnitude 5.0 releases about 32 times more energy.
Tectonic setting
27 km
from the nearest mapped plate boundary, between the Sunda and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
10 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 4 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.6 on September 17, 2006. 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 255 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.7226 km SSW of Singaparna, IndonesiaJuly 17, 2006 · 130 km NW of this epicenter
- 7.6233 km S of Pundong, IndonesiaSeptember 11, 1921 · 247 km E of this epicenter
- 7.487 km SSW of Srandakan, IndonesiaJuly 23, 1943 · 215 km NE of this epicenter
- 7.1138 km SSE of Pundong, IndonesiaSeptember 10, 1926 · 259 km E of this epicenter
- 6.9south of Java, IndonesiaJuly 24, 1979 · 155 km SW of this epicenter
- 6.992 km S of Pundong, IndonesiaSeptember 27, 1937 · 256 km NE of this epicenter
- 6.5260 km SSW of Kroya, IndonesiaSeptember 7, 1974 · 14 km N of this epicenter
- 6.5south of Java, IndonesiaDecember 12, 1924 · 292 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,046 recorded deaths. The most severe:
- 2006M7.7
Java
17 Jul 2006 · 130 km away
802 deaths$55 million damagetsunami
- 1943M8.1
Java: Jogyakarta
23 Jul 1943 · 182 km away · intensity VIII
213 deathsSevere damage ($5–24M)
- 1979M6.1
Java
2 Nov 1979 · 254 km away
30 deaths$16 million damage
- 1937M7.2
Java: Jogyakarta: Klumpit,Prambanan
27 Sep 1937 · 206 km away · intensity IX
1 deathSevere damage ($5–24M)
- 1980M5.8
Java: Tasikmalaja
16 Apr 1980 · 211 km away
Moderate damage ($1–5M)
- 1863
Java: Banyumas
31 Jul 1863 · 288 km away
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.