Reviewed by USGSIndia21y ago
M4.4 earthquake 155 km SW of Port Blair, India
Monday, April 18, 2005, 09:50:10 UTC · 10.692°N, 91.719°E
A magnitude 4.4 earthquake struck 155 km SW of Port Blair, India on Monday, April 18, 2005, 09:50:10 UTC, at a depth of 28.1 km (shallow).
- Magnitude
- 4.4
- Light · mb
- Depth
- 28 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
60 tons of TNT
That is about 1/251 of the Hiroshima bomb. A magnitude 5.0 releases about 8 times more energy.
Tectonic setting
15 km
from the nearest mapped plate boundary, between the Indian and Burma plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
28 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 M4.6 on April 18, 2005. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 3.9166 km SW of Port Blair, India21y ago · 18 km S of this epicenter
- 4.0129 km SW of Port Blair, India21y ago · 37 km E of this epicenter
- 4.5157 km SW of Port Blair, India21y ago · 3 km W of this epicenter
- 4.0167 km SW of Bamboo Flat, India21y ago · 19 km W of this epicenter
- 4.6160 km SW of Bamboo Flat, India21y ago · 13 km NW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 209 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.043 km N of Bamboo Flat, IndiaJune 26, 1941 · 185 km NE of this epicenter
- 6.6Nicobar Islands, India regionDecember 26, 2004 · 214 km S of this epicenter
- 6.5152 km NNE of Bamboo Flat, IndiaSeptember 13, 2002 · 299 km NE of this epicenter
- 6.5171 km S of Port Blair, IndiaApril 19, 1936 · 128 km SE of this epicenter
- 6.3273 km SSE of Port Blair, IndiaOctober 21, 1916 · 255 km SE of this epicenter
- 6.3Nicobar Islands, India regionOctober 25, 1970 · 296 km SE of this epicenter
- 6.3Nicobar Islands, India regionSeptember 15, 1964 · 251 km SE of this epicenter
- 6.353 km W of Bamboo Flat, IndiaAugust 8, 1945 · 126 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 3 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2 recorded deaths. The most severe:
- 2002M6.5
Andaman Islands: Rongat, Diglipur,Ariel Bay
13 Sep 2002 · 299 km away
2 deathsModerate damage ($1–5M)tsunami
- 1941M8.0
Andaman Islands,Madras; Sri Lanka: Colombo
26 Jun 1941 · 170 km away
Extreme damage ($25M+)tsunami
- 1881M7.9
Andaman I,Nicobar I
31 Dec 1881 · 254 km away
Severe damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.