7.2 quake rattles lower Colorado River area in Mexico

Sunday, April 4, 2010

USGS intensity map of the Baja California, Mexico earthquake
Map of southern California and northern Baja California with earthquakes shortly after the main earthquake

The US Geological Survey (USGS) on the afternoon of Easter Sunday monitored a large earthquake in the southern Imperial Valley south of Mexicali, Mexico near the Colorado River, at about 15:40 PDT (22:40 UTC). It was felt throughout the surrounding area for a great distance, with shaking said to have lasted for about a minute.

The USGS reports that the epicenter was 26 kilometers (16 miles) south-southwest of Guadalupe Victoria, Baja California, Mexico, and 173 kilometers (108 miles) east-southeast of Tijuana, Baja California, at a depth of 10 kilometers (6.2 miles).

According to witnesses, the quake was felt as far away as Los Angeles and San Diego, California. The Reuters news agency reports numerous aftershocks, and the USGS has reported at least three at this time. One reached magnitude 5.1, another one, which occurred in the same place as the first quake, reached 5.4, and a third in Sonora reached 5.1. A Wikinews correspondent in the Los Angeles area, Mike Morales, felt the earthquake and reports, "I was at home and then I almost thought it was vertigo, but really it was the earthquake. I'm surprised I could feel it here; it was in Baja California."

One casualty has been reported in Mexicali, and the Los Angeles Fire Department has been put on alert. It was reported that a number of people were stuck in an elevator in Disneyland, Anaheim.

There were about 30 earthquakes of magnitude 3.0 or greater in southern California and northern Baja California in the two hours immediately following the earthquake (see map below and right). Nine of them were of 4.0 or greater. A small number were in the immediate vicinity of the main earthquake. The majority of them were centered on an area about 40 miles to the northwest. The rest were scattered over a wide area of the southern California desert, as much as 100 miles from the main earthquake. Seismologists have not yet announced what relationship, if any, these earthquakes have to the main earthquake.

According to the Chilean Oceanographic and Hydrographic Service (SHOA), no tsunamis are expected to reach the coast of Chile.