Reviewed by USGSIndonesia30y ago
M4.1 earthquake 70 km WNW of Insrom, Indonesia
Wednesday, March 20, 1996, 08:03:26 UTC · 0.827°S, 135.480°E
A magnitude 4.1 earthquake struck 70 km WNW of Insrom, Indonesia on Wednesday, March 20, 1996, 08:03:26 UTC, at a depth of 33.0 km (shallow).
- Magnitude
- 4.1
- 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
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
91 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 M5.3 on March 25, 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 243 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 · 207 km SE of this epicenter
- 8.11996 Biak, Indonesia EarthquakeFebruary 17, 1996 · 164 km E of this epicenter
- 7.955 km S of Biak, IndonesiaSeptember 12, 1979 · 113 km SE of this epicenter
- 7.736 km NNE of Nabire, IndonesiaJanuary 13, 1916 · 251 km S of this epicenter
- 7.65 km SW of Manokwari, IndonesiaApril 27, 1944 · 162 km W of this epicenter
- 7.6138 km SW of Insrom, IndonesiaMay 27, 1947 · 127 km SW of this epicenter
- 7.3195 km E of Biak, IndonesiaApril 2, 1947 · 264 km E of this epicenter
- 7.182 km SE of Biak, IndonesiaJune 22, 1957 · 159 km SE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 9 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 · 57 km away · intensity VII
250 deathsSevere damage ($5–24M)tsunami
- 1996M8.2
New Guinea: Irian Jaya: Biak, Supiori
17 Feb 1996 · 164 km away · intensity IX
164 deaths$4 million damagetsunami
- 1979M7.9
New Guinea: Irian Jaya
12 Sep 1979 · 113 km away
115 deathsSevere damage ($5–24M)tsunami
- 1957M7.3
New Guinea: Irian Jaya
22 Jun 1957 · 185 km away
Severe damage ($5–24M)tsunami
- 1914M8.1
New Guinea: Irian Jaya: Japen
26 May 1914 · 197 km away · intensity IX
Moderate damage ($1–5M)tsunami
- 1985M7.1
New Guinea: Irian Jaya: Manokwari
17 Nov 1985 · 110 km away · intensity VIII
Limited damage (under $1M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.