Reviewed by USGSChina18y ago
M3.8 earthquake 38 km WNW of Tianpeng, China
Wednesday, July 9, 2008, 00:09:17 UTC · 31.155°N, 103.590°E
A magnitude 3.8 earthquake struck 38 km WNW of Tianpeng, China on Wednesday, July 9, 2008, 00:09:17 UTC, at a depth of 12.2 km (shallow).
- Magnitude
- 3.8
- Minor · mb
- Depth
- 12 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
8 tons of TNT
That is about 1/1,992 of the Hiroshima bomb. A magnitude 5.0 releases about 63 times more energy.
Tectonic setting
313 km
from the nearest mapped plate boundary, between the Eurasian and Yangtze plates. Earthquakes this far from a boundary happen on faults inside a plate, often less frequently but sometimes strongly.
Depth: shallow
12 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 5 M2.5+ earthquakes within 50 km in the following 30 days; the largest was M4.6 on July 28, 2008. Most nearby activity right after a large earthquake is aftershocks, which usually become less frequent over days and weeks.
- 4.058 km WNW of Tianpeng, China18y ago · 24 km W of this epicenter
- 4.633 km NNW of Tianpeng, China18y ago · 27 km NE of this epicenter
- 3.9eastern Sichuan, China18y ago · 49 km SW of this epicenter
- 4.446 km NNW of Tianpeng, China18y ago · 34 km NE of this epicenter
- 4.645 km N of Linqiong, China18y ago · 41 km SW of this epicenter
Regional history
Past M5+ earthquakes within 300 km
USGS lists 147 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 7.958 km W of Tianpeng, ChinaMay 12, 2008 · 31 km SW of this epicenter
- 7.4203 km NW of Kangding, ChinaFebruary 6, 1973 · 287 km W of this epicenter
- 7.4101 km WNW of Jiangyou, ChinaAugust 25, 1933 · 89 km N of this epicenter
- 7.1150 km WNW of Kangding, ChinaAugust 30, 1904 · 289 km W of this epicenter
- 7.119 km WSW of Kangding, ChinaApril 14, 1955 · 220 km SW of this epicenter
- 7.0184 km NW of Kangding, ChinaMarch 24, 1923 · 270 km W of this epicenter
- 6.9121 km NNW of Jiangyou, ChinaAugust 16, 1976 · 185 km N of this epicenter
- 6.892 km SSW of Luocheng, ChinaMay 16, 1936 · 282 km S of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 49 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700, which together caused about 129,418 recorded deaths. The most severe:
- 2008M7.9
Sichuan Province
12 May 2008 · 27 km away · intensity IX
87,652 deaths$86 billion damagetsunami
- 1879M8.0
Gansu Province
1 Jul 1879 · 250 km away · intensity XI
22,000 deathsExtreme damage ($25M+)
- 1933M7.4
Sichuan Province
25 Aug 1933 · 89 km away · intensity X
9,300 deathsExtreme damage ($25M+)
- 1923M7.3
Sichuan Province
24 Mar 1923 · 249 km away · intensity X
4,800 deathsSevere damage ($5–24M)
- 1816M6.5
Sichuan Province
8 Dec 1816 · 276 km away · intensity VIII
2,854 deathsSevere damage ($5–24M)
- 1881M6.5
Gansu Province
20 Jul 1881 · 288 km away · intensity VIII
480 deathsSevere damage ($5–24M)
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.