Magnitude5.5

Reviewed by USGSIndonesia43y ago

M5.5 earthquake 56 km SW of Komodo, Indonesia

Wednesday, November 16, 1983, 22:07:21 UTC · 8.980°S, 119.156°E

A magnitude 5.5 earthquake struck 56 km SW of Komodo, Indonesia on Wednesday, November 16, 1983, 22:07:21 UTC, at a depth of 79.4 km (intermediate). It is the strongest earthquake within 300 km since an M6.4 on October 31, 1983.

Magnitude
5.5
Moderate · mw
Depth
79 km
Intermediate
Felt reports
0
Did You Feel It?
Est. shaking
IV
Light (ShakeMap)
PAGER alert
None
Not issued
Tsunami
No flag
USGS feed

Outlined circle: this earthquakeDashed circle: 75 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)

In context

How big was it, and why here?

Energy released

3 kilotons of TNT

That is about 1/6 of the Hiroshima bomb. It released about 6 times the energy of a magnitude 5.0.

Tectonic setting

160 km

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

Depth: intermediate

79 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 75 km

USGS lists 1 M2.5+ earthquake within 75 km in the following 30 days; the largest was M4.2 on December 14, 1983. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M51h6h1d3d7d14d30dMainshock M5.5
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 4.288 km SSW of Komodo, Indonesia43y ago · 43 km S of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 317 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 9 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 689 recorded deaths. The most severe:

  1. 1820M7.5

    Sulawesi: Makasar

    29 Dec 1820 · 221 km away · intensity X

    500 deathsModerate damage ($1–5M)tsunami

  2. 1977M8.3

    Sunda Islands

    19 Aug 1977 · 257 km away

    189 deaths$1 million damagetsunami

  3. 1828

    Sulawesi

    29 Dec 1828 · 221 km away · intensity IX

    Severe damage ($5–24M)tsunami

  4. 1982M5.6

    Flores Islands: Ruteng

    6 Aug 1982 · 170 km away

    Moderate damage ($1–5M)

  5. 1836M7.5

    Flores Sea

    28 Nov 1836 · 91 km away

    Limited damage (under $1M)tsunami

  6. 1954M6.8

    Sumabawa: Bima,Raba

    2 Nov 1954 · 110 km away · intensity VIII

    Limited damage (under $1M)

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

Nearby trackers

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