Magnitude6.7

Reviewed by USGS92y ago

M6.7 earthquake in Mariana Islands region

Friday, October 18, 1935, 11:05:26 UTC · 12.523°N, 141.428°E

A magnitude 6.7 earthquake struck in Mariana Islands region on Friday, October 18, 1935, 11:05:26 UTC, at a depth of 20.0 km (shallow). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.

Magnitude
6.7
Strong · mw
Depth
20 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

188 kilotons of TNT

That is about 12 times the Hiroshima bomb. It released about 394 times the energy of a magnitude 5.0.

Tectonic setting

155 km

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

Depth: shallow

20 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 has not published any M2.5+ earthquake within 100 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 14 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 6 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:

  1. 1849M7.5

    Guam

    25 Jan 1849 · 261 km away · intensity IX

    Severe damage ($5–24M)tsunami

  2. 1892M7.5

    Guam

    16 May 1892 · 261 km away · intensity VIII

    Moderate damage ($1–5M)tsunami

  3. 1825

    Ladrones Island

    Apr 1825 · 261 km away · intensity VIII

    Moderate damage ($1–5M)tsunami

  4. 1834

    Agana

    May 1834 · 261 km away

    Moderate damage ($1–5M)

  5. 1903

    Guam

    10 Feb 1903 · 261 km away · intensity VII

    Limited damage (under $1M)tsunami

  6. 1809

    Guam

    1809 · 261 km away

    tsunami

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

Nearby trackers

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