Seismologists studying 7.2 quake and aftershocks centered in geothermal field

In Baja California, a magnitude 7.2 quake that shook the southwestern U.S. and northwestern Mexico Easter Sunday was centered in an active geothermal area 42 miles south-southeast of Calexico known as Cerro Prieto. The geothermal fields supply electricity to a large portion of Baja California, including the city of Mexicali and the area ranks as second largest in the world in terms of geothermal power generated. On March 27, a magnitude 3.5 quake hit about 29 miles south-southeast of Calexico. At the time, the Cerro Prieto area was reported to have seen about a dozen small quakes in the previous week ranging from magnitude 2.2 to 3.9. Seismologists are studying several smaller quakes north of the Mexico border in the Imperial Valley that may be part of the aftershock sequence. The imperial Valley is developing its geothermal resources, and there were no reports of any effects on energy production or potential in either area.