Reviewed by USGSIndonesia38y ago
M4.3 earthquake 177 km NW of Tobelo, Indonesia
Friday, April 7, 1989, 16:04:04 UTC · 2.961°N, 126.990°E
A magnitude 4.3 earthquake struck 177 km NW of Tobelo, Indonesia on Friday, April 7, 1989, 16:04:04 UTC, at a depth of 88.6 km (intermediate).
- Magnitude
- 4.3
- Light · mb
- Depth
- 89 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
43 tons of TNT
That is about 1/354 of the Hiroshima bomb. A magnitude 5.0 releases about 11 times more energy.
Tectonic setting
68 km
from the nearest mapped plate boundary, between the Sunda and Birds Head plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: intermediate
89 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 M4.1 on May 3, 1989. 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 1,097 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.8161 km SE of Sarangani, PhilippinesApril 1, 1936 · 160 km NW of this epicenter
- 7.790 km NE of Tobelo, IndonesiaSeptember 8, 1966 · 178 km E of this epicenter
- 7.7121 km E of Bitung, IndonesiaAugust 10, 1968 · 186 km SW of this epicenter
- 7.6101 km SE of Sarangani, PhilippinesDecember 16, 1910 · 218 km NW of this epicenter
- 7.6223 km ESE of Sarangani, PhilippinesJanuary 30, 1969 · 193 km N of this epicenter
- 7.564 km NNW of Ternate, IndonesiaJune 25, 1907 · 182 km S of this epicenter
- 7.5146 km NW of Ternate, IndonesiaAugust 14, 1986 · 140 km S of this epicenter
- 7.5210 km SSE of Sarangani, PhilippinesAugust 17, 1912 · 132 km NW 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 3,096 recorded deaths. The most severe:
- 1856
Sangihe Pulau (Volcanic)
2 Mar 1856 · 183 km away
2,806 deathsSevere damage ($5–24M)tsunami
- 1913M7.8
Sangihe Island
14 Mar 1913 · 283 km away · intensity IX
138 deathsModerate damage ($1–5M)tsunami
- 1845M7.0
N Sulawesi: Menado, Tikala, Tomohon
8 Feb 1845 · 289 km away · intensity IX
118 deathsModerate damage ($1–5M)tsunami
- 1855
Maluku: Ternate Island
14 Jul 1855 · 243 km away · intensity IX
34 deathsModerate damage ($1–5M)
- 1858M7.3
N. Moluccas Islands
13 Dec 1858 · 244 km away
Severe damage ($5–24M)tsunami
- 1989M5.6
Molucca Passage: Morotai, Tanawangu
8 Mar 1989 · 232 km away
Severe damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.