Reviewed by USGSIndonesia30y ago
M4.6 earthquake in Biak region, Indonesia
Friday, April 5, 1996, 11:45:48 UTC · 0.982°S, 136.676°E
A magnitude 4.6 earthquake struck in Biak region, Indonesia on Friday, April 5, 1996, 11:45:48 UTC, at a depth of 33.0 km (shallow). It is the strongest earthquake within 300 km since an M4.7 on April 2, 1996.
- Magnitude
- 4.6
- Light · mb
- Depth
- 33 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 earthquakeDashed circle: 50 km aftershock search area
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
69 km
from the nearest mapped plate boundary, between the Birds Head and Caroline plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: shallow
33 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 lists 4 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M5.1 on May 4, 1996. 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 316 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.21914 Biak EarthquakeMay 26, 1914 · 115 km S of this epicenter
- 8.11996 Biak, Indonesia EarthquakeFebruary 17, 1996 · 32 km E of this epicenter
- 7.955 km S of Biak, IndonesiaSeptember 12, 1979 · 105 km SW of this epicenter
- 7.8230 km W of Abepura, IndonesiaJune 1, 1906 · 269 km SE of this epicenter
- 7.736 km NNE of Nabire, IndonesiaJanuary 13, 1916 · 258 km SW of this epicenter
- 7.65 km SW of Manokwari, IndonesiaApril 27, 1944 · 295 km W of this epicenter
- 7.6138 km SW of Insrom, IndonesiaMay 27, 1947 · 209 km SW of this epicenter
- 7.3195 km E of Biak, IndonesiaApril 2, 1947 · 130 km E of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 10 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 529 recorded deaths. The most severe:
- 1864M7.8
Irian Jaya: Manokwari
23 May 1864 · 186 km away · intensity VII
250 deathsSevere damage ($5–24M)tsunami
- 1996M8.2
New Guinea: Irian Jaya: Biak, Supiori
17 Feb 1996 · 32 km away · intensity IX
164 deaths$4 million damagetsunami
- 1979M7.9
New Guinea: Irian Jaya
12 Sep 1979 · 105 km away
115 deathsSevere damage ($5–24M)tsunami
- 1957M7.3
New Guinea: Irian Jaya
22 Jun 1957 · 68 km away
Severe damage ($5–24M)tsunami
- 1914M8.1
New Guinea: Irian Jaya: Japen
26 May 1914 · 99 km away · intensity IX
Moderate damage ($1–5M)tsunami
- 1921
New Guinea: Irian Jaya: Sentani
10 Oct 1921 · 278 km away · intensity VII
Moderate damage ($1–5M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.