Reviewed by USGSNorthern Mariana Islands31y ago
M4.3 earthquake in Pagan region, Northern Mariana Islands
Wednesday, August 30, 1995, 09:06:41 UTC · 18.753°N, 145.459°E
A magnitude 4.3 earthquake struck in Pagan region, Northern Mariana Islands on Wednesday, August 30, 1995, 09:06:41 UTC, at a depth of 602.0 km (deep).
- Magnitude
- 4.3
- Light · mb
- Depth
- 602 km
- Deep
- 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
90 km
from the nearest mapped plate boundary, between the Philippine Sea and Mariana plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: deep
602 km
Deep earthquakes (over 300 km) happen deep inside subducting plates. They rarely cause damage, but can be felt faintly over very large distances.
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 September 10, 1995. 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 257 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.7Mariana Islands regionDecember 28, 1940 · 220 km E of this epicenter
- 7.2Pagan region, Northern Mariana IslandsOctober 24, 1930 · 134 km E of this epicenter
- 7.1Pagan region, Northern Mariana IslandsAugust 23, 1995 · 28 km NW of this epicenter
- 6.9Maug Islands region, Northern Mariana IslandsMarch 7, 1962 · 50 km NW of this epicenter
- 6.7Pagan region, Northern Mariana IslandsNovember 15, 1954 · 40 km NE of this epicenter
- 6.7Pagan region, Northern Mariana IslandsFebruary 1, 1956 · 48 km W of this epicenter
- 6.7Mariana Islands regionSeptember 16, 1986 · 112 km NE of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 1 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1902M8.1
Agana
22 Sep 1902 · 101 km away · intensity IX
Severe damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.