Magnitude4.6

Reviewed by USGSCosta Rica16d ago

M4.6 earthquake 28 km S of Quepos, Costa Rica

Thursday, September 10, 2026, 18:04:04 UTC · 9.172°N, 84.147°W

A magnitude 4.6 earthquake struck 28 km S of Quepos, Costa Rica on Thursday, September 10, 2026, 18:04:04 UTC, at a depth of 35.0 km (shallow). USGS received 1 “Did You Feel It?” report, with a maximum reported intensity of II (weak). It is the strongest earthquake within 300 km since an M5.0 on September 10, 2026.

Magnitude
4.6
Light · mb
Depth
35 km
Shallow
Felt reports
1
Max intensity II
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

120 tons of TNT

That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.

Tectonic setting

66 km

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

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

Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.

PlaceIntensityReportsDistance
La Suiza, Cartago, Costa RicaII · Weak1101 km
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 since this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 454 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 49 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 910 recorded deaths. The most severe:

  1. 1910M6.4

    Cartago, San Jose

    4 May 1910 · 93 km away

    700 deathsSevere damage ($5–24M)

  2. 1991M7.6

    Limon, Pandora; Panama

    22 Apr 1991 · 131 km away · intensity X

    90 deaths$510 million damagetsunami

  3. 1952

    Costa Rica

    30 Dec 1952 · 144 km away

    29 deaths

  4. 1973M6.5

    Tilaran, Arenal, Rio Chiquito

    14 Apr 1973 · 180 km away

    26 deathsUnder $1 million damage

  5. 2009M6.1

    La Paz

    8 Jan 2009 · 111 km away

    23 deaths$502 million damage

  6. 1955M5.8

    Costa Rica

    1 Sep 1955 · 100 km away

    10 deathsModerate damage ($1–5M)

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

Nearby trackers

Closest city pages