Magnitude7.0

Reviewed by USGSChina107y ago

M7.0 earthquake 139 km ENE of Baiyin, China

Saturday, December 25, 1920, 11:33:20 UTC · 37.243°N, 105.474°E

A magnitude 7.0 earthquake struck 139 km ENE of Baiyin, China on Saturday, December 25, 1920, 11:33:20 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.9 on December 16, 1920.

Magnitude
7.0
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

461 kilotons of TNT

That is about 31 times the Hiroshima bomb. It released about 966 times the energy of a magnitude 5.0.

Tectonic setting

651 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 100 km

USGS lists 2 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M6.1 on December 28, 1920. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M6M71h6h1d3d7d14d30dMainshock M7.0
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 6.0116 km SW of Yinchuan, China107y ago · 42 km N of this epicenter
  2. 6.1138 km SSW of Yinchuan, China107y ago · 20 km N of this epicenter

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 10 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 362,942 recorded deaths. The most severe:

  1. 1920M8.3

    Gansu Province, Shanxi Province

    16 Dec 1920 · 73 km away · intensity XII

    235,502 deaths$25 million damagetsunami

  2. 1718M7.5

    Gansu Province

    19 Jun 1718 · 251 km away · intensity X

    73,000 deathsExtreme damage ($25M+)

  3. 1739M8.0

    Ningxia

    3 Jan 1739 · 205 km away · intensity X

    50,000 deathsExtreme damage ($25M+)

  4. 1765M6.5

    Gansu Province: Wushan, Gangu

    2 Sep 1765 · 275 km away · intensity IX

    2,068 deathsExtreme damage ($25M+)

  5. 1709M7.5

    Ningxia

    14 Oct 1709 · 23 km away · intensity X

    2,032 deathsExtreme damage ($25M+)

  6. 1852M6.0

    Ningxia

    26 May 1852 · 37 km away · intensity VIII

    300 deathsSevere damage ($5–24M)

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

Nearby trackers

Closest city pages