M3.9 earthquake 173 km SE of Kokopo, Papua New Guinea

Monday, September 25, 1995, 17:02:13 UTC · 5.388°S, 153.440°E

A magnitude 3.9 earthquake struck 173 km SE of Kokopo, Papua New Guinea on Monday, September 25, 1995, 17:02:13 UTC, at a depth of 104.0 km (intermediate).

Magnitude: 3.9; Minor · mb
Depth: 104 km; Intermediate
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: 50 km aftershock search area

In context

How big was it, and why here?

Energy released

11 tons of TNT

That is about 1/1,410 of the Hiroshima bomb. A magnitude 5.0 releases about 45 times more energy.

Tectonic setting

2 km

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

Depth: intermediate

104 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 50 km

USGS lists 6 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M5.5 on October 21, 1995. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.

Time after the mainshock on a logarithmic scale (first hours stretched), magnitude on the vertical axis. M2.5+ events from USGS.

Regional history

Past M5+ earthquakes within 300 km

USGS lists 1,498 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 37 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 532 recorded deaths. The most severe:

1937
Keravia, Rabaul, Kokopo
28 May 1937 · 185 km away · intensity VIII
507 deathsLimited damage (under $1M)tsunami
1983M6.4
Ulawun, Rabaul
22 Dec 1983 · 174 km away · intensity V
10 deaths$25 million damage
1939M7.7
Bougainville Island
30 Jan 1939 · 286 km away
5 deathsModerate damage ($1–5M)tsunami
1941M7.4
Bismarck Sea
13 Jan 1941 · 203 km away
4 deathsModerate damage ($1–5M)tsunami
1971M7.9
New Ireland: Bougainville
14 Jul 1971 · 52 km away · intensity IX
3 deathsUnder $1 million damagetsunami
1985M7.1
New Britain: Bialla, Piona
10 May 1985 · 266 km away · intensity VIII
1 death$1 million damage

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

Nearby trackers