Magnitude7.2

Reviewed by USGSIndonesia89y ago

M7.2 earthquake 182 km WNW of Tobelo, Indonesia

Monday, October 10, 1938, 20:48:07 UTC · 2.400°N, 126.514°E

A magnitude 7.2 earthquake struck 182 km WNW of Tobelo, Indonesia on Monday, October 10, 1938, 20:48:07 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M7.8 on April 1, 1936.

Magnitude
7.2
Major · mw
Depth
15 km
Shallow
Felt reports
0
Did You Feel It?
Est. shaking
V
Moderate (ShakeMap)
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeDashed circle: 200 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

1.0 megatons of TNT

That is about 68 times the Hiroshima bomb. It released about 2,138 times the energy of a magnitude 5.0.

Tectonic setting

36 km

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

Depth: shallow

15 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 200 km

USGS lists 1 M2.5+ earthquake within 200 km in the following 30 days; the largest was M6.1 on October 11, 1938. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M6M71h6h1d3d7d14d30dMainshock M7.2
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 6.1199 km NE of Laikit, Laikit II (Dimembe), Indonesia89y ago · 32 km NW of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 63 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 20 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2,965 recorded deaths. The most severe:

  1. 1856

    Sangihe Pulau (Volcanic)

    2 Mar 1856 · 181 km away

    2,806 deathsSevere damage ($5–24M)tsunami

  2. 1845M7.0

    N Sulawesi: Menado, Tikala, Tomohon

    8 Feb 1845 · 211 km away · intensity IX

    118 deathsModerate damage ($1–5M)tsunami

  3. 1855

    Maluku: Ternate Island

    14 Jul 1855 · 198 km away · intensity IX

    34 deathsModerate damage ($1–5M)

  4. 1932M7.7

    Sulawesi: Kakas,Langowan,Poso,Tondano

    14 May 1932 · 235 km away · intensity VII

    7 deathsSevere damage ($5–24M)tsunami

  5. 1858M7.3

    N. Moluccas Islands

    13 Dec 1858 · 166 km away

    Severe damage ($5–24M)tsunami

  6. 1889M8.0

    N. Moluccas Islands

    6 Sep 1889 · 158 km away

    Moderate damage ($1–5M)tsunami

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

Nearby trackers

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