Tectonic Summary
Magnitude 6.3 NORTHERN IRAN
2004 May 28 12:38:46 UTC
Preliminary Earthquake Report
U.S. Geological Survey, National Earthquake Information Center
World Data Center for Seismology, Denver
Iran lies in the wide boundary that separates the Arabian and Eurasian plates.
In the region of Iran, the Arabian plate moves northward with respect to the Eurasian plate with a
velocity of about 20 mm/year. The Elburz (Alborz) Mountains, in which the May 28, 2004,
earthquake occurred, is one of several zones of high tectonic activity within the
overall plate-boundary zone. The earthquake was generated as the result
of reverse slip on a west-northwest trending fault.
Most previous earthquakes in the Elburz Mountains have resulted
from either reverse faulting or strike-slip faulting.
The May 28, 2004, earthquake occurred about 175 km
east-southeast of the disastrous magnitude 7.4 earthquake
of June 20, 1990, which is estimated to have killed over 40,000 people.