Reviewed by USGSPapua New Guinea51y ago
M4.6 earthquake 168 km SW of Panguna, Papua New Guinea
Tuesday, December 2, 1975, 12:19:43 UTC · 7.480°S, 154.500°E
A magnitude 4.6 earthquake struck 168 km SW of Panguna, Papua New Guinea on Tuesday, December 2, 1975, 12:19:43 UTC, at a depth of 16.0 km (shallow). It is the strongest earthquake within 300 km since an M5.4 on November 23, 1975.
- Magnitude
- 4.6
- Light · mb
- Depth
- 16 km
- Shallow
- 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
120 tons of TNT
That is about 1/126 of the Hiroshima bomb. A magnitude 5.0 releases about 4 times more energy.
Tectonic setting
50 km
from the nearest mapped plate boundary, between the North Bismarck and Solomon Sea plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
16 km
Shallow earthquakes (under 70 km) produce the strongest surface shaking for their size, so they are the ones most likely to cause damage near the epicenter.
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 424 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.01971 New Britain EarthquakeJuly 14, 1971 · 235 km N of this epicenter
- 7.956 km WSW of Panguna, Papua New GuineaJuly 20, 1975 · 116 km NE of this epicenter
- 7.885 km S of Panguna, Papua New GuineaJanuary 30, 1939 · 107 km NE of this epicenter
- 7.794 km SSW of Panguna, Papua New GuineaJuly 20, 1975 · 83 km NE of this epicenter
- 7.7152 km SE of Kokopo, Papua New GuineaSeptember 29, 1946 · 284 km NW of this epicenter
- 7.5199 km SSE of Kokopo, Papua New GuineaAugust 17, 1972 · 238 km NW of this epicenter
- 7.3166 km SE of Kokopo, Papua New GuineaFebruary 12, 1968 · 263 km NW of this epicenter
- 7.361 km NW of Gizo, Solomon IslandsApril 19, 1936 · 222 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 8 recorded deaths. The most severe:
- 1939M7.7
Bougainville Island
30 Jan 1939 · 107 km away
5 deathsModerate damage ($1–5M)tsunami
- 1971M7.9
New Ireland: Bougainville
14 Jul 1971 · 230 km away · intensity IX
3 deathsUnder $1 million damagetsunami
- 1975M7.9
Bismarck Sea: Bougainville
20 Jul 1975 · 116 km away · intensity VIII
Severe damage ($5–24M)tsunami
- 1959M7.3
Solomon Islands
17 Aug 1959 · 165 km away
Severe damage ($5–24M)tsunami
- 1974M7.1
Solomon Islands
1 Feb 1974 · 122 km away · intensity VI
Moderate damage ($1–5M)tsunami
- 1968M7.8
New Ireland
12 Feb 1968 · 263 km away · intensity VIII
Limited damage (under $1M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.