Magnitude6.1

Reviewed by USGSChina79y ago

M6.1 earthquake 35 km SSE of Zhaotong, China

Friday, October 8, 1948, 19:02:00 UTC · 27.050°N, 103.908°E

A magnitude 6.1 earthquake struck 35 km SSE of Zhaotong, China on Friday, October 8, 1948, 19:02:00 UTC, at a depth of 35.0 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on May 16, 1936.

Magnitude
6.1
Strong · mw
Depth
35 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
—
No ShakeMap
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeDashed circle: 100 km aftershock search area

In context

How big was it, and why here?

Energy released

19 kilotons of TNT

That is about the energy of the Hiroshima bomb. It released about 39 times the energy of a magnitude 5.0.

Tectonic setting

123 km

from the nearest mapped plate boundary, between the Eurasian and Yangtze plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.

Depth: shallow

35 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 M5.9 on October 10, 1948. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M61h6h1d3d7d14d30dMainshock M6.1
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 5.929 km ESE of Zhaotong, China79y ago · 24 km NE of this epicenter

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:

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 23 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 32,123 recorded deaths. The most severe:

  1. 1850M7.5

    Sichuan: Xichang

    12 Sep 1850 · 179 km away · intensity X

    20,650 deathsExtreme damage ($25M+)

  2. 1833M8.0

    Yunnan Province

    6 Sep 1833 · 225 km away · intensity XI

    6,700 deathsExtreme damage ($25M+)tsunami

  3. 1713M6.8

    Yunnan Province: S Of Xundian

    26 Feb 1713 · 197 km away · intensity IX

    2,100 deathsExtreme damage ($25M+)

  4. 1917M6.8

    Yunnan Province

    30 Jul 1917 · 106 km away · intensity IX

    1,800 deathsExtreme damage ($25M+)

  5. 1725M6.0

    Yunnan Province: Songming, Yiliang

    8 Jan 1725 · 231 km away · intensity VIII

    614 deathsSevere damage ($5–24M)

  6. 1935M6.0

    Sichuan Province

    18 Dec 1935 · 186 km away · intensity VIII

    100 deathsModerate damage ($1–5M)tsunami

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

Nearby trackers

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