Magnitude7.8

Reviewed by USGSChina95y ago

M7.8 earthquake 108 km WSW of Laojunmiao, China

Sunday, December 25, 1932, 02:04:30 UTC · 39.462°N, 96.562°E

A magnitude 7.8 earthquake struck 108 km WSW of Laojunmiao, China on Sunday, December 25, 1932, 02:04:30 UTC, at a depth of 15.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.

Magnitude
7.8
Major · 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 earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

8.7 megatons of TNT

That is about 576 times the Hiroshima bomb. It released about 18,197 times the energy of a magnitude 5.0.

Tectonic setting

1,025 km

from the nearest mapped plate boundary, between the Amur and Eurasian 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 lists 1 M2.5+ earthquake within 200 km in the following 30 days; the largest was M5.6 on December 25, 1932. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M6M7M81h6h1d3d7d14d30dMainshock M7.8
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 5.6140 km SW of Laojunmiao, China95y ago · 55 km S of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 3 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 2 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 311 recorded deaths. The most severe:

  1. 1932M7.6

    Gansu Province

    25 Dec 1932 · 29 km away · intensity X

    275 deathsSevere damage ($5–24M)

  2. 1785M6.0

    Gansu Province: Huihuipu

    18 Apr 1785 · 132 km away · intensity VIII

    36 deathsModerate damage ($1–5M)

NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.

Nearby trackers

Closest city pages