Reviewed by USGSPapua New Guinea40y ago
M4.5 earthquake 84 km NNE of Finschhafen, Papua New Guinea
Saturday, April 4, 1987, 06:00:55 UTC · 5.868°S, 148.167°E
A magnitude 4.5 earthquake struck 84 km NNE of Finschhafen, Papua New Guinea on Saturday, April 4, 1987, 06:00:55 UTC, at a depth of 235.6 km (intermediate). It is the strongest earthquake within 300 km since an M4.6 on March 29, 1987.
- Magnitude
- 4.5
- Light · mb
- Depth
- 236 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 earthquake
In context
How big was it, and why here?
Energy released
85 tons of TNT
That is about 1/178 of the Hiroshima bomb. A magnitude 5.0 releases about 6 times more energy.
Tectonic setting
155 km
from the nearest mapped plate boundary, between the South Bismarck and Woodlark plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
236 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 has not published any M2.5+ earthquake within 50 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 575 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.01906 Papua New Guinea EarthquakeSeptember 14, 1906 · 113 km W of this epicenter
- 7.638 km NW of Finschhafen, Papua New GuineaOctober 2, 1906 · 81 km SW of this epicenter
- 7.548 km NW of Finschhafen, Papua New GuineaMay 12, 1938 · 78 km SW of this epicenter
- 7.549 km WSW of Wau, Papua New GuineaFebruary 26, 1963 · 276 km SW of this epicenter
- 7.532 km SSW of Kimbe, Papua New GuineaDecember 28, 1945 · 208 km E of this epicenter
- 7.492 km WSW of Kandrian, Papua New GuineaMay 6, 1947 · 95 km SE of this epicenter
- 7.4177 km SW of Kavieng, Papua New GuineaJanuary 13, 1905 · 296 km NE of this epicenter
- 7.454 km NNW of Finschhafen, Papua New GuineaFebruary 8, 1987 · 58 km SW of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 20 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 3 recorded deaths. The most severe:
- 1987M7.6
Huon Peninsula, Umboi Island
8 Feb 1987 · 58 km away · intensity VII
3 deaths$3 million damagetsunami
- 1906M8.0
New Britain
14 Sep 1906 · 156 km away
Severe damage ($5–24M)tsunami
- 1857M8.0
Bismarck Sea
17 Apr 1857 · 135 km away
Moderate damage ($1–5M)tsunami
- 1873M8.0
Maclay Coast
1873 · 243 km away · intensity IX
Moderate damage ($1–5M)tsunami
- 1987M7.7
New Britain: Kandrian, Kimbte
16 Oct 1987 · 108 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1984M6.6
Karkar
27 Mar 1984 · 295 km away · intensity VIII
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.