Reviewed by USGSIndia region21y ago
M5.4 earthquake in Nicobar Islands, India region
Wednesday, August 3, 2005, 23:43:47 UTC · 6.725°N, 92.667°E
A magnitude 5.4 earthquake struck in Nicobar Islands, India region on Wednesday, August 3, 2005, 23:43:47 UTC, at a depth of 5.1 km (shallow). It is the strongest earthquake within 300 km since an M5.8 on July 30, 2005.
- Magnitude
- 5.4
- Moderate · mwb
- Depth
- 5 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: 75 km aftershock search area
In context
How big was it, and why here?
Energy released
2 kilotons of TNT
That is about 1/8 of the Hiroshima bomb. It released about 4 times the energy of a magnitude 5.0.
Tectonic setting
38 km
from the nearest mapped plate boundary, between the Burma and Indian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
5 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 75 km
USGS lists 2 M2.5+ earthquakes within 75 km in the following 30 days; the largest was M4.4 on August 5, 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 512 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 · 38 km NE of this epicenter
- 7.2Nicobar Islands, India regionJuly 24, 2005 · 143 km N of this epicenter
- 7.0190 km WNW of Sabang, IndonesiaMay 17, 1955 · 133 km E of this epicenter
- 6.975 km WSW of Banda Aceh, IndonesiaAugust 23, 1936 · 279 km SE of this epicenter
- 6.968 km WSW of Sabang, IndonesiaApril 4, 1983 · 253 km SE of this epicenter
- 6.8238 km WNW of Sabang, IndonesiaJanuary 20, 1917 · 96 km E of this epicenter
- 6.7off the west coast of northern SumatraJanuary 1, 2005 · 185 km S of this epicenter
- 6.6Nicobar Islands, India regionApril 7, 1973 · 144 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 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 · 235 km away · intensity VIII
9 deathsModerate damage ($1–5M)tsunami
- 1881M7.9
Andaman I,Nicobar I
31 Dec 1881 · 201 km away
Severe damage ($5–24M)tsunami
- 1983M6.6
Sumatera: Banda Aceh
4 Apr 1983 · 253 km away · intensity VII
$1 million damage
- 1982M6.3
Little Nicobar Island
20 Jan 1982 · 149 km away · intensity VIII
Moderate damage ($1–5M)
- 2005M7.2
Andaman Islands, Nicobar Islands
24 Jul 2005 · 143 km away
Limited damage (under $1M)
- 1847
Little Nicobar Island
31 Oct 1847 · 129 km away · intensity X
Limited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.