Reviewed by USGSBangladesh104y ago
M6.9 earthquake 9 km NNE of Netrakona, Bangladesh
Sunday, September 9, 1923, 22:03:46 UTC · 24.969°N, 90.752°E
A magnitude 6.9 earthquake struck 9 km NNE of Netrakona, Bangladesh on Sunday, September 9, 1923, 22:03:46 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.1 on July 8, 1918.
- Magnitude
- 6.9
- Strong · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VIII
- Severe (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
362 kilotons of TNT
That is about 24 times the Hiroshima bomb. It released about 759 times the energy of a magnitude 5.0.
Tectonic setting
221 km
from the nearest mapped plate boundary, between the Eurasian and Indian plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
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 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 2 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
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 1,669 recorded deaths. The most severe:
- 1897M8.0
Assam; Bangladesh
12 Jun 1897 · 115 km away · intensity X
1,542 deathsExtreme damage ($25M+)tsunami
- 1885M6.9
Unnamed location
14 Jul 1885 · 128 km away · intensity VII
75 deathsModerate damage ($1–5M)
- 1923M6.9
Mymensingh
9 Sep 1923 · 0 km away
50 deathsModerate damage ($1–5M)
- 1869
Assam: Cachar,Silchar
10 Jan 1869 · 184 km away
2 deathsSevere damage ($5–24M)
- 1918M7.6
Srimangal
8 Jul 1918 · 58 km away
Moderate damage ($1–5M)
- 1842M6.0
Unnamed location
11 Nov 1842 · 186 km away
Limited damage (under $1M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.