Reviewed by USGSChina80y ago
M7.6 earthquake in Qinghai-Sichuan border region, China
Monday, March 17, 1947, 08:19:37 UTC · 33.498°N, 99.491°E
A magnitude 7.6 earthquake struck in Qinghai-Sichuan border region, China on Monday, March 17, 1947, 08:19:37 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.8 on January 7, 1937.
- Magnitude
- 7.6
- Major · 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 earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
3.5 megatons of TNT
That is about 235 times the Hiroshima bomb. It released about 7,413 times the energy of a magnitude 5.0.
Tectonic setting
631 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 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 18 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8Southern Qinghai, ChinaJanuary 7, 1937 · 258 km NW of this epicenter
- 7.0184 km NW of Kangding, ChinaMarch 24, 1923 · 272 km SE of this epicenter
- 6.5296 km NE of Qamdo, ChinaAugust 25, 1919 · 45 km SW of this epicenter
- 6.3Southern Qinghai, ChinaJuly 26, 1935 · 139 km E of this epicenter
- 6.1Southern Qinghai, ChinaApril 28, 1915 · 259 km W of this epicenter
- 6.1Southern Qinghai, ChinaMay 5, 1915 · 274 km W of this epicenter
- 6.0282 km WSW of Xining, ChinaJanuary 10, 1940 · 206 km N of this epicenter
- 5.9132 km SW of Linxia Chengguanzhen, ChinaDecember 6, 1931 · 281 km NE 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 8,958 recorded deaths. The most severe:
- 1923M7.3
Sichuan Province
24 Mar 1923 · 263 km away · intensity X
4,800 deathsSevere damage ($5–24M)
- 1816M6.5
Sichuan Province
8 Dec 1816 · 259 km away · intensity VIII
2,854 deathsSevere damage ($5–24M)
- 1811M6.5
Sichuan Province: E. Of Ganze
27 Sep 1811 · 214 km away · intensity VIII
480 deathsModerate damage ($1–5M)
- 1904M6.0
Sichuan Province
30 Aug 1904 · 288 km away · intensity VIII
400 deathsModerate damage ($1–5M)
- 1738M6.5
Qinghai Province
1738 · 269 km away · intensity VIII
336 deaths
- 1834M5.5
Qinghai Province
1834 · 238 km away · intensity VII
88 deaths
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.