Reviewed by USGSPapua New Guinea44y ago
M3.9 earthquake 147 km ESE of Kokopo, Papua New Guinea
Saturday, April 16, 1983, 17:01:03 UTC · 4.881°S, 153.490°E
A magnitude 3.9 earthquake struck 147 km ESE of Kokopo, Papua New Guinea on Saturday, April 16, 1983, 17:01:03 UTC, at a depth of 84.3 km (intermediate).
- Magnitude
- 3.9
- Minor · mb
- Depth
- 84 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
36 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
84 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 1 M2.5+ earthquake within 50 km in the following 30 days; the largest was M4.6 on April 17, 1983. 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 856 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.21919 Papua New Guinea EarthquakeMay 6, 1919 · 42 km E of this epicenter
- 8.11971 Bougainville EarthquakeJuly 26, 1971 · 34 km W of this epicenter
- 8.01971 New Britain EarthquakeJuly 14, 1971 · 77 km SE of this epicenter
- 8.060 km SE of Kokopo, Papua New GuineaJanuary 1, 1916 · 97 km W of this epicenter
- 7.956 km WSW of Panguna, Papua New GuineaJuly 20, 1975 · 257 km SE of this epicenter
- 7.874 km SSW of Kokopo, Papua New GuineaFebruary 2, 1920 · 163 km W of this epicenter
- 7.7152 km SE of Kokopo, Papua New GuineaSeptember 29, 1946 · 40 km SW of this epicenter
- 7.6157 km ESE of Kokopo, Papua New GuineaMarch 18, 1983 · 10 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 30 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 525 recorded deaths. The most severe:
- 1937
Keravia, Rabaul, Kokopo
28 May 1937 · 158 km away · intensity VIII
507 deathsLimited damage (under $1M)tsunami
- 1983M6.4
Ulawun, Rabaul
22 Dec 1983 · 188 km away · intensity V
10 deaths$25 million damage
- 1941M7.4
Bismarck Sea
13 Jan 1941 · 176 km away
4 deathsModerate damage ($1–5M)tsunami
- 1971M7.9
New Ireland: Bougainville
14 Jul 1971 · 82 km away · intensity IX
3 deathsUnder $1 million damagetsunami
- 1878
Bismarck Sea
4 Feb 1878 · 154 km away
1 deathtsunami
- 1975M7.9
Bismarck Sea: Bougainville
20 Jul 1975 · 257 km away · intensity VIII
Severe damage ($5–24M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.