Historic Earthquakes: Tectonic Summary

2002 March 25 14:56:33 UTC

This shallow earthquake occurred near the boundary of the Eurasian and Indian tectonic plates. The two plates are converging at a rate of about 1.8 inches (4.5 centimeters) per year.

This convergence generates complex stresses in the region resulting from both subduction and rotation of continental blocks. Major tectonic features in the region include the Darvaz-Karakul fault, the Harat fault, the Chaman fault, and the Indus-Tsangpo suture zone.

The earthquake occurred within the Earth's crust, at a depth of 8 kilometers. Seismic waves recorded world-wide imply that the earthquake resulted from slip on a north-trending reverse fault. Several mapped faults in the region have orientations similar to the fault that caused the earthquake, although seismologists have not yet associated the earthquake with a specific mapped fault.

The Hindu Kush region is highly seismic. On average, there are about five magnitude 5 or greater earthquakes per year whose epicenters are within 100 miles (161 kilometers) of this event. Earthquake depths in this region range from the surface to depths of 205 miles (330 kilometers).

The earthquake is the result of geologic processes that have been active for millions of years; its occurrence is independent of the recent bombing in Afghanistan.