Magnitude6.9

Reviewed by USGSIndonesia35y ago

M6.9 earthquake 160 km NNE of Maumere, Indonesia

Friday, June 7, 1991, 11:51:25 UTC · 7.204°S, 122.533°E

A magnitude 6.9 earthquake struck 160 km NNE of Maumere, Indonesia on Friday, June 7, 1991, 11:51:25 UTC, at a depth of 536.4 km (deep). It is the strongest earthquake within 300 km since an M7.1 on May 24, 1990.

Magnitude
6.9
Strong · mw
Depth
536 km
Deep
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

338 kilotons of TNT

That is about 22 times the Hiroshima bomb. It released about 708 times the energy of a magnitude 5.0.

Tectonic setting

73 km

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

Depth: deep

536 km

Deep earthquakes (over 300 km) happen deep inside subducting plates. They rarely cause damage, but can be felt faintly over very large distances.

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 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M5.3 on July 6, 1991. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

M3M4M5M6M71h6h1d3d7d14d30dMainshock M6.9
Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.
  1. 5.3153 km N of Maumere, Indonesia35y ago · 20 km W of this epicenter

Regional history

Past M5+ earthquakes within 300 km

USGS lists 228 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 418 recorded deaths. The most severe:

  1. 1896

    Timor: Alor Island

    18 Apr 1896 · 271 km away · intensity VIII

    250 deathsModerate damage ($1–5M)

  2. 1987M6.5

    Timor: Pantar, Mount Sirung

    26 Nov 1987 · 213 km away

    125 deaths$5 million damagetsunami

  3. 1991M6.5

    Timor: Kalabahi, Dili

    4 Jul 1991 · 257 km away

    28 deaths$8 million damage

  4. 1982M5.9

    Flores Island: Eastern

    25 Dec 1982 · 147 km away

    13 deaths$1 million damagetsunami

  5. 1961M6.5

    Flores: Endeh

    16 Mar 1961 · 125 km away · intensity VIII

    2 deathsModerate damage ($1–5M)

  6. 1982M5.6

    Flores Islands: Ruteng

    6 Aug 1982 · 252 km away

    Moderate damage ($1–5M)

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

Nearby trackers

Closest city pages