Reviewed by USGSIndia56y ago
M6.3 earthquake 253 km E of Port Blair, India
Sunday, March 28, 1971, 08:23:20 UTC · 11.882°N, 95.058°E
A magnitude 6.3 earthquake struck 253 km E of Port Blair, India on Sunday, March 28, 1971, 08:23:20 UTC, at a depth of 16.3 km (shallow). It is the strongest earthquake within 300 km since an M6.7 on February 14, 1967.
- Magnitude
- 6.3
- Strong · mw
- Depth
- 16 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 earthquake
In context
How big was it, and why here?
Energy released
40 kilotons of TNT
That is about 3 times the Hiroshima bomb. It released about 83 times the energy of a magnitude 5.0.
Tectonic setting
3 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
16 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 100 km
USGS has not published any M2.5+ earthquake within 100 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 38 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 · 263 km W of this epicenter
- 6.7188 km WSW of Dawei, Burma (Myanmar)February 14, 1967 · 257 km NE of this epicenter
- 6.4Andaman Islands, India regionOctober 17, 1922 · 79 km NE of this epicenter
- 6.4230 km W of Dawei, Burma (Myanmar)July 28, 1964 · 272 km NE of this epicenter
- 6.3229 km S of Pyapon, MyanmarJune 18, 1957 · 270 km N of this epicenter
- 6.2179 km NNE of Bamboo Flat, IndiaNovember 16, 1962 · 266 km NW of this epicenter
- 6.2112 km NE of Bamboo Flat, IndiaJuly 4, 1917 · 195 km W of this epicenter
- 6.168 km N of Bamboo Flat, IndiaJuly 27, 1944 · 247 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1941M8.0
Andaman Islands,Madras; Sri Lanka: Colombo
26 Jun 1941 · 265 km away
Extreme damage ($25M+)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.