QuakeScout
Magnitude4.2

Reviewed by USGSPeru52y ago

M4.2 earthquake 115 km SW of Asia, Peru

Saturday, October 12, 1974, 01:08:01 UTC · 13.408°S, 77.402°W

A magnitude 4.2 earthquake struck 115 km SW of Asia, Peru on Saturday, October 12, 1974, 01:08:01 UTC, at a depth of 33.0 km (shallow).

Magnitude
4.2
Light · mb
Depth
33 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 earthquake

In context

How big was it, and why here?

Energy released

30 tons of TNT

That is about 1/500 of the Hiroshima bomb. A magnitude 5.0 releases about 16 times more energy.

Tectonic setting

57 km

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

Depth: shallow

33 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 has not published any M2.5+ earthquake within 50 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 39 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

  1. 8.221 km SE of Huacho, PeruMay 24, 1940 · 244 km N of this epicenter
  2. 7.677 km WSW of Callao, PeruOctober 3, 1974 · 134 km N of this epicenter
  3. 6.710 km SSW of Huacho, PeruMay 24, 1940 · 247 km N of this epicenter
  4. 6.691 km SSW of Santiago, PeruJune 25, 1930 · 225 km SE of this epicenter
  5. 6.3144 km W of Paracas, PeruApril 6, 1922 · 78 km S of this epicenter
  6. 6.360 km W of San Juan, PeruAugust 25, 1942 · 277 km SE of this epicenter
  7. 6.329 km ESE of Santiago, PeruDecember 10, 1950 · 231 km SE of this epicenter
  8. 6.35 km SSW of Mariatana, PeruJanuary 5, 1974 · 168 km NE of this epicenter

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 29 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 6,134 recorded deaths. The most severe:

  1. 1746M8.0

    Lima, Callao

    29 Oct 1746 · 159 km away · intensity XI

    5,941 deathsExtreme damage ($25M+)tsunami

  2. 1974M8.1

    Lima, Callao

    3 Oct 1974 · 133 km away · intensity IX

    78 deaths$10 million damagetsunami

  3. 1813

    Ica

    30 Mar 1813 · 230 km away · intensity VII

    32 deathsModerate damage ($1–5M)

  4. 1942M8.2

    Ica, Nazca

    24 Aug 1942 · 233 km away · intensity IX

    30 deathsSevere damage ($5–24M)tsunami

  5. 1828M8.3

    Lima, Callao

    30 Mar 1828 · 149 km away · intensity VII

    30 deathsModerate damage ($1–5M)tsunami

  6. 1974M6.3

    Lima, Yauyos

    5 Jan 1974 · 168 km away

    10 deathsSevere damage ($5–24M)

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

Nearby trackers

Closest city pages