QuakeScout
Magnitude7.7

Reviewed by USGSIndonesia60y ago

M7.7 earthquake 90 km NE of Tobelo, Indonesia

Thursday, September 8, 1966, 21:15:56 UTC · 2.388°N, 128.490°E

A magnitude 7.7 earthquake struck 90 km NE of Tobelo, Indonesia on Thursday, September 8, 1966, 21:15:56 UTC, at a depth of 115.0 km (intermediate). No earthquake of this size or larger appears within 300 km in the USGS catalog since 1900.

Magnitude
7.7
Major · mw
Depth
115 km
Intermediate
Felt reports
0
Did You Feel It?
Est. shaking
VII
Very strong (ShakeMap)
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

5.5 megatons of TNT

That is about 368 times the Hiroshima bomb. It released about 11,614 times the energy of a magnitude 5.0.

Tectonic setting

47 km

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

Depth: intermediate

115 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 200 km

USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 92 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:

  1. 7.564 km NNW of Ternate, IndonesiaJune 25, 1907 · 187 km SW of this epicenter
  2. 7.5273 km N of Tobelo, IndonesiaOctober 23, 1914 · 209 km N of this epicenter
  3. 7.2182 km WNW of Tobelo, IndonesiaOctober 10, 1938 · 220 km W of this epicenter
  4. 7.1129 km WNW of Ternate, IndonesiaMay 3, 1925 · 275 km SW of this epicenter
  5. 7.086 km NNW of Tobelo, IndonesiaMarch 27, 1949 · 93 km W of this epicenter
  6. 7.0146 km E of Laikit, Laikit II (Dimembe), IndonesiaOctober 5, 1936 · 259 km W of this epicenter
  7. 6.8227 km ESE of Sarangani, PhilippinesNovember 15, 1944 · 272 km NW of this epicenter

History · NOAA

Deadliest earthquakes in this area

NOAA’s significant-earthquake database lists 8 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 34 recorded deaths. The most severe:

  1. 1855

    Maluku: Ternate Island

    14 Jul 1855 · 221 km away · intensity IX

    34 deathsModerate damage ($1–5M)

  2. 1889M8.0

    N. Moluccas Islands

    6 Sep 1889 · 293 km away

    Moderate damage ($1–5M)tsunami

  3. 1840

    Maluku: Ternate Island

    14 Feb 1840 · 219 km away

    Moderate damage ($1–5M)tsunami

  4. 1910M6.7

    Sulawesi-N. Moluccas Islands

    18 Dec 1910 · 244 km away · intensity VIII

    Limited damage (under $1M)tsunami

  5. 1907M7.9

    Djailolo Gilolo

    25 Jun 1907 · 226 km away

  6. 1846M7.3

    N. Moluccas Islands

    25 Jan 1846 · 225 km away

    tsunami

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

Nearby trackers

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