Magnitude6.4

Reviewed by USGSIndonesia58y ago

M6.4 earthquake 199 km N of Tobelo, Indonesia

Thursday, February 20, 1969, 09:55:37 UTC · 3.531°N, 128.129°E

A magnitude 6.4 earthquake struck 199 km N of Tobelo, Indonesia on Thursday, February 20, 1969, 09:55:37 UTC, at a depth of 43.9 km (shallow). It is the strongest earthquake within 300 km since an M6.8 on February 3, 1969.

Magnitude
6.4
Strong · mw
Depth
44 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 earthquakeDashed circle: 100 km aftershock search area

In context

How big was it, and why here?

Energy released

67 kilotons of TNT

That is about 4 times the Hiroshima bomb. It released about 140 times the energy of a magnitude 5.0.

Tectonic setting

63 km

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

Depth: shallow

44 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 lists 4 M2.5+ earthquakes within 100 km in the following 30 days; the largest was M6.4 on February 20, 1969. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 138 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 7 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 2,806 recorded deaths. The most severe:

  1. 1856

    Sangihe Pulau (Volcanic)

    2 Mar 1856 · 292 km away

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

  2. 1936M7.7

    Talaud Islands

    1 Apr 1936 · 210 km away · intensity IX

    Moderate damage ($1–5M)tsunami

  3. 1910M6.7

    Sulawesi-N. Moluccas Islands

    18 Dec 1910 · 136 km away · intensity VIII

    Limited damage (under $1M)tsunami

  4. 1957M7.6

    Philippines

    24 Sep 1957 · 230 km away

  5. 1910M7.5

    Talaud Islands

    16 Dec 1910 · 260 km away

  6. 1969M7.5

    Talaud Islands, Mindanao, Visayan

    30 Jan 1969 · 163 km away

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

Nearby trackers

Closest city pages