Reviewed by USGSPhilippines109y ago
M6.7 earthquake 37 km ESE of Sarangani, Philippines
Thursday, August 15, 1918, 17:30:11 UTC · 5.232°N, 125.751°E
A magnitude 6.7 earthquake struck 37 km ESE of Sarangani, Philippines on Thursday, August 15, 1918, 17:30:11 UTC, at a depth of 15.0 km (shallow). It is the strongest earthquake within 300 km since an M8.3 on August 15, 1918.
- Magnitude
- 6.7
- Strong · mw
- Depth
- 15 km
- Shallow
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- VI
- Strong (ShakeMap)
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquakeDashed circle: 100 km aftershock search areaColoured lines: estimated shaking intensity (USGS ShakeMap)
In context
How big was it, and why here?
Energy released
194 kilotons of TNT
That is about 13 times the Hiroshima bomb. It released about 407 times the energy of a magnitude 5.0.
Tectonic setting
196 km
from the nearest mapped plate boundary, between the Philippine Sea and Sunda plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
15 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 100 km
USGS lists 1 M2.5+ earthquake within 100 km in the following 30 days; the largest was M6.1 on September 5, 1918. 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 17 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.31918 Mindanao, Philippines EarthquakeAugust 15, 1918 · 197 km W of this epicenter
- 7.947 km ESE of Kalbay, PhilippinesMarch 14, 1913 · 38 km NE of this epicenter
- 7.6101 km SE of Sarangani, PhilippinesDecember 16, 1910 · 69 km SE of this epicenter
- 7.5210 km SSE of Sarangani, PhilippinesAugust 17, 1912 · 187 km S of this epicenter
- 7.5273 km N of Tobelo, IndonesiaOctober 23, 1914 · 276 km SE of this epicenter
- 6.937 km S of Daliao, PhilippinesJanuary 31, 1917 · 99 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 13 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 3,007 recorded deaths. The most severe:
- 1856
Sangihe Pulau (Volcanic)
2 Mar 1856 · 176 km away
2,806 deathsSevere damage ($5–24M)tsunami
- 1913M7.8
Sangihe Island
14 Mar 1913 · 43 km away · intensity IX
138 deathsModerate damage ($1–5M)tsunami
- 1918M8.3
Mindanao: Cotabato
15 Aug 1918 · 197 km away · intensity X
52 deathsSevere damage ($5–24M)tsunami
- 1917M6.4
S Mindanao: Glan,Glan Padidu,Tuyan
31 Jan 1917 · 119 km away · intensity IX
7 deathsModerate damage ($1–5M)tsunami
- 1870
Mindanao: Davao,Blanco
4 Nov 1870 · 200 km away
4 deathsModerate damage ($1–5M)
- 1871
W Mindanao: Cotabato,Polloc Harbor
8 Dec 1871 · 296 km away · intensity IX
Severe damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.