Magnitude2.6

Reviewed by USGSCalifornia46y ago

M2.6 earthquake 67 km W of Indianola, California

Saturday, December 20, 1980, 08:00:33 UTC · 40.786°N, 125.023°W

A magnitude 2.6 earthquake struck 67 km W of Indianola, California on Saturday, December 20, 1980, 08:00:33 UTC, at a depth of 36.7 km (shallow).

Magnitude
2.6
Minor · md
Depth
37 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: 50 km aftershock search area

In context

How big was it, and why here?

Energy released

133 kg of TNT

That is about 1/113,329 of the Hiroshima bomb. A magnitude 5.0 releases about 3,589 times more energy.

Tectonic setting

7 km

from the nearest mapped plate boundary, between the Juan de Fuca and North American plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.

Depth: shallow

37 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 50 km

USGS lists 6 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.8 on December 23, 1980. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 132 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 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2 recorded deaths. The most severe:

  1. 1954M6.6

    Humboldt County

    21 Dec 1954 · 95 km away

    1 death$2 million damage

  2. 1932M6.5

    Eureka

    6 Jun 1932 · 62 km away · intensity VIII

    1 deathModerate damage ($1–5M)

  3. 1980M7.2

    North Coast

    8 Nov 1980 · 74 km away · intensity VII

    $2 million damage

  4. 1865

    Fort Humboldt, Eureka

    1 Oct 1865 · 50 km away · intensity IX

    Moderate damage ($1–5M)

  5. 1922M7.6

    Northern

    31 Jan 1922 · 47 km away

    Limited damage (under $1M)

  6. 1923M7.1

    Northern

    22 Jan 1923 · 34 km away · intensity VIII

    Limited damage (under $1M)tsunami

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

Nearby trackers

Closest city pages