M4.1 earthquake 114 km ESE of Kokopo, Papua New Guinea

Sunday, January 28, 2001, 13:30:17 UTC · 4.833°S, 153.178°E

A magnitude 4.1 earthquake struck 114 km ESE of Kokopo, Papua New Guinea on Sunday, January 28, 2001, 13:30:17 UTC, at a depth of 72.5 km (intermediate).

Magnitude: 4.1; Light · mb
Depth: 73 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

21 tons of TNT

That is about 1/707 of the Hiroshima bomb. A magnitude 5.0 releases about 22 times more energy.

Tectonic setting

10 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

73 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 7 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M5.1 on February 10, 2001. 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 1,821 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 40 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 530 recorded deaths. The most severe:

1937
Keravia, Rabaul, Kokopo
28 May 1937 · 125 km away · intensity VIII
507 deathsLimited damage (under $1M)tsunami
1983M6.4
Ulawun, Rabaul
22 Dec 1983 · 158 km away · intensity V
10 deaths$25 million damage
1941M7.4
Bismarck Sea
13 Jan 1941 · 143 km away
4 deathsModerate damage ($1–5M)tsunami
1971M7.9
New Ireland: Bougainville
14 Jul 1971 · 109 km away · intensity IX
3 deathsUnder $1 million damagetsunami
2000M8.0
New Ireland, Duke Of York
16 Nov 2000 · 132 km away
2 deathsModerate damage ($1–5M)tsunami
1996M7.2
Bougainville Island
29 Apr 1996 · 275 km away
1 deathModerate damage ($1–5M)

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

Nearby trackers