Historic Earthquakes: Tectonic Summary

Magnitude 6.0 YUNNAN, CHINA
2003 July 21 15:16:31 UTC

The July 21 earthquake occurred as the result of strike-slip faulting. Southwestern China is traversed by several major, seismically active, strike-slip faults, and many destructive earthquakes have occurred on lesser strike-slip faults. The epicenter of the July 21 earthquake is about 100 km north-northeast of the large Red River fault and about 100 km west of the large Anninghe fault. The causative fault of the July 21 earthquake has not yet been identified.

In a broad sense, strike-slip faults and earthquakes in southwestern China result from the eastward motion of the Earth's crust that is driven by the collision of the Indian and Eurasian continental plates beneath the Himalaya Mountains and the Tibetan Plateau farther to the west.

Destructive earthquakes within the past century,
centered within 300 km of the July 21, 2003 earthquake
Date Magnitude Fatalities Injuries Damage
2001 10 27 5.7 At least 1 220 3,400 buildings destroyed in Yongsheng area
2000 08 21 4.9 1 406 169,000 homeless, extensive damage in Wuding County
2000 01 14 5.4 7 2,528 92,479 homeless, 41,000 houses destroyed in Yunnan Province
1998 11 19 5.2 5 1,543 12,000 homes destroyed, 16,000 buildings damaged
1996 02 03 6.4 322 16,925 358,000 housing units collapsed, 654,000 more damaged
1995 10 23 5.8 81 800 200 houses damaged or destroyed in the Wuding area
1970 01 04 7.5 ~10,000 Unknown Roughly $5 to $25 million damage
1925 03 16 7.0 ~5,000 7,200 76,000 houses collapsed in Dali area