Reviewed by USGS12y ago
M4.9 earthquake in Guam region
Wednesday, November 5, 2014, 07:28:03 UTC · 13.924°N, 145.300°E
A magnitude 4.9 earthquake struck in Guam region on Wednesday, November 5, 2014, 07:28:03 UTC, at a depth of 112.3 km (intermediate). USGS received 5 “Did You Feel It?” reports, with a maximum reported intensity of III (weak). It is the strongest earthquake within 300 km since an M5.7 on October 6, 2014.
- Magnitude
- 4.9
- Light · mb
- Depth
- 112 km
- Intermediate
- Felt reports
- 5
- Max intensity III
- 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
338 tons of TNT
That is about 1/45 of the Hiroshima bomb. A magnitude 5.0 releases about 1 times more energy.
Tectonic setting
138 km
from the nearest mapped plate boundary, between the Philippine Sea and Mariana plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: intermediate
112 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
Reports sent by people to USGS, grouped by place (most reports first). Intensity uses the Modified Mercalli scale (I–X): what people felt, not the magnitude.
| Place | Intensity | Reports | Distance |
|---|---|---|---|
| 96929<br>0.320 | II · Weak | 2 | 126 km |
| 96914<br>0.330 | III · Weak | 1 | 140 km |
| 96913<br>0.330 | II · Weak | 1 | 133 km |
| 96915<br>0.330 | II · Weak | 1 | 143 km |
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 M4.0 on November 27, 2014. 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 648 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.832 km S of Inarajan Village, GuamAugust 8, 1993 · 118 km SW of this epicenter
- 7.6198 km E of Saipan, Northern Mariana IslandsApril 5, 1990 · 281 km NE of this epicenter
- 7.120 km SSW of Merizo Village, GuamApril 26, 2002 · 119 km SW of this epicenter
- 7.0176 km ESE of San Jose Village, Northern Mariana IslandsMay 18, 1913 · 197 km E of this epicenter
- 7.098 km SSE of Inarajan Village, GuamDecember 9, 1909 · 173 km S of this epicenter
- 7.032 km NNE of Yigo Village, GuamOctober 26, 1912 · 39 km W of this epicenter
- 7.0233 km ESE of Saipan, Northern Mariana IslandsJune 14, 1942 · 285 km E of this epicenter
- 7.069 km SSE of Inarajan Village, GuamOctober 12, 2001 · 142 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 15 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1993M7.8
Tuman Bay, Apra Harbor
8 Aug 1993 · 118 km away · intensity IX
$250 million damagetsunami
- 1849M7.5
Guam
25 Jan 1849 · 216 km away · intensity IX
Severe damage ($5–24M)tsunami
- 1909M8.0
Guam
9 Dec 1909 · 162 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 1892M7.5
Guam
16 May 1892 · 216 km away · intensity VIII
Moderate damage ($1–5M)tsunami
- 2001M7.0
Guam
12 Oct 2001 · 142 km away · intensity VIII
Moderate damage ($1–5M)
- 1825
Ladrones Island
Apr 1825 · 216 km away · intensity VIII
Moderate damage ($1–5M)tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.