Magnitude3.7

Reviewed by USGSChile21y ago

M3.7 earthquake 133 km E of Iquique, Chile

Sunday, October 2, 2005, 11:29:46 UTC · 20.276°S, 68.875°W

A magnitude 3.7 earthquake struck 133 km E of Iquique, Chile on Sunday, October 2, 2005, 11:29:46 UTC, at a depth of 112.4 km (intermediate).

Magnitude
3.7
Minor · mb
Depth
112 km
Intermediate
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

5 tons of TNT

That is about 1/2,814 of the Hiroshima bomb. A magnitude 5.0 releases about 89 times more energy.

Tectonic setting

135 km

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

Depth: intermediate

112 km

Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.

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 3 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.2 on October 16, 2005. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M41h6h1d3d7d14d30dMainshock M3.7
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 4.2146 km E of Iquique, Chile21y ago · 35 km N of this epicenter
  2. 3.5126 km E of Iquique, Chile21y ago · 7 km W of this epicenter
  3. 4.0120 km ENE of Iquique, Chile21y ago · 41 km NW of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 482 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 47 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 27,407 recorded deaths. The most severe:

  1. 1868M8.5

    Arica

    13 Aug 1868 · 290 km away · intensity XI

    25,000 deaths$300 million damagetsunami

  2. 1877M8.3

    Off North Coast

    10 May 1877 · 217 km away · intensity XI

    2,385 deaths$2 million damagetsunami

  3. 2005M7.7

    Tarapaca

    13 Jun 2005 · 47 km away

    11 deaths$5 million damage

  4. 1987M6.9

    Arica, Iquique

    8 Aug 1987 · 182 km away · intensity VII

    5 deaths$1 million damage

  5. 1953M7.4

    Northern

    7 Dec 1953 · 204 km away

    3 deaths$7 million damage

  6. 1967M7.5

    Northern

    21 Dec 1967 · 171 km away

    1 deathModerate damage ($1–5M)tsunami

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

Nearby trackers

Closest city pages