Reviewed by USGSIndia region21y ago
M4.3 earthquake in Nicobar Islands, India region
Wednesday, March 16, 2005, 05:44:22 UTC · 8.608°N, 93.689°E
A magnitude 4.3 earthquake struck in Nicobar Islands, India region on Wednesday, March 16, 2005, 05:44:22 UTC, at a depth of 30.0 km (shallow).
- Magnitude
- 4.3
- 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
43 tons of TNT
That is about 1/354 of the Hiroshima bomb. A magnitude 5.0 releases about 11 times more energy.
Tectonic setting
51 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 5 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.3 on April 14, 2005. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.3Nicobar Islands, India region21y ago · 42 km S of this epicenter
- 4.2Nicobar Islands, India region21y ago · 23 km S of this epicenter
- 4.0Nicobar Islands, India region21y ago · 32 km SE of this epicenter
- 3.8Nicobar Islands, India region21y ago · 20 km N of this epicenter
- 4.1Nicobar Islands, India region21y ago · 19 km NW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 481 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 · 205 km SW of this epicenter
- 7.0190 km WNW of Sabang, IndonesiaMay 17, 1955 · 199 km S of this epicenter
- 6.8238 km WNW of Sabang, IndonesiaJanuary 20, 1917 · 178 km S of this epicenter
- 6.6Nicobar Islands, India regionDecember 26, 2004 · 148 km W of this epicenter
- 6.6249 km NW of Sabang, IndonesiaMarch 5, 1921 · 134 km S of this epicenter
- 6.5253 km WNW of Sabang, IndonesiaNovember 21, 1907 · 238 km S of this epicenter
- 6.5171 km S of Port Blair, IndiaApril 19, 1936 · 198 km NW of this epicenter
- 6.4284 km W of Sabang, IndonesiaJanuary 2, 2005 · 269 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 6 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 · 300 km away · intensity VIII
9 deathsModerate damage ($1–5M)tsunami
- 1881M7.9
Andaman I,Nicobar I
31 Dec 1881 · 139 km away
Severe damage ($5–24M)tsunami
- 1982M6.3
Little Nicobar Island
20 Jan 1982 · 188 km away · intensity VIII
Moderate damage ($1–5M)
- 2005M7.2
Andaman Islands, Nicobar Islands
24 Jul 2005 · 182 km away
Limited damage (under $1M)
- 1847
Little Nicobar Island
31 Oct 1847 · 142 km away · intensity X
Limited damage (under $1M)tsunami
- 1955M7.3
Little Nicobar Island
17 May 1955 · 237 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.