Reviewed by USGSBhutan86y ago
M6.4 earthquake 29 km SE of Trashigang, Bhutan
Tuesday, January 21, 1941, 12:41:45 UTC · 27.169°N, 91.794°E
A magnitude 6.4 earthquake struck 29 km SE of Trashigang, Bhutan on Tuesday, January 21, 1941, 12:41:45 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.0 on July 2, 1930.
- Magnitude
- 6.4
- Strong · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VII
- Very strong (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
67 kilotons of TNT
That is about 4 times the Hiroshima bomb. It released about 140 times the energy of a magnitude 5.0.
Tectonic setting
15 km
from the nearest mapped plate boundary, between the Eurasian and Indian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
15 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 lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.0 on January 27, 1941. 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 15 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.124 km N of Kishorganj, BangladeshJuly 8, 1918 · 297 km S of this epicenter
- 7.028 km SSW of Lakhipur, IndiaJuly 2, 1930 · 222 km SW of this epicenter
- 6.99 km NNE of Netrakona, BangladeshSeptember 9, 1923 · 266 km SW of this epicenter
- 6.634 km NNW of Tawang, IndiaDecember 3, 1915 · 75 km N of this epicenter
- 6.510 km S of Mokokchūng, IndiaMay 12, 1906 · 290 km E of this epicenter
- 5.922 km NE of Tura, IndiaMarch 6, 1933 · 221 km SW of this epicenter
- 5.83 km E of Rangia, IndiaNovember 9, 1932 · 81 km S of this epicenter
- 5.823 km N of Diphu, IndiaMarch 21, 1937 · 207 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 8 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 1,862 recorded deaths. The most severe:
- 1897M8.0
Assam; Bangladesh
12 Jun 1897 · 169 km away · intensity X
1,542 deathsExtreme damage ($25M+)tsunami
- 1915M7.0
Tibet (Xizang Province)
3 Dec 1915 · 261 km away · intensity IX
170 deathsModerate damage ($1–5M)
- 1806M7.7
Tibet (Xizang Province): Shannan (Lhoka)
11 Jun 1806 · 149 km away
100 deathsModerate damage ($1–5M)
- 1923M6.9
Mymensingh
9 Sep 1923 · 266 km away
50 deathsModerate damage ($1–5M)
- 1930M7.1
Dhubri,Assam
2 Jul 1930 · 258 km away · intensity IX
Severe damage ($5–24M)
- 1713
Arunachal; Bhutan
1713 · 125 km away
Severe damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.