Series of temblors, including a 5.0, shake Yuma area Tuesday

A 5.0 magnitude aftershock shook the Yuma area at 3:41 p.m. Tuesday, according to the National Earthquake Information Center based in Denver.

"This is a very active area, the boundary between the North American and Pacific plates," said Dale Grant, a geophysicist with the NEIC. "It's not very unusual. It's a part of an aftershock series."

Grant added that the latest temblor is part of a continuing swarm that began on Feb. 9 with the first earthquake of 5.5 magnitude on the Richter scale.

"The initial shock typically releases the most energy," Grant said. "After that it's the Earth trying to come to equilibrium with itself."

Grant added that when a quake breaks there is still energy in the ground and there is always movement on the fault boundaries trying to release the pressure. Aftershocks could continue for a couple of weeks or a couple of months. No injuries or major damage was reported, he noted.

Dr. Earl Burnett, a part-time geology instructor at Arizona Western College, said the Ensenada Earthquake Center showed data disclosing that Tuesday's aftershock was 10 miles closer to Yuma than previous aftershocks or the initial quake.

"The other shocks were associated with the Cerro Prieto fault," Barnett said. "This one may be on the southern end of the Imperial fault."

Burnett cautioned that people should be a little skeptical about the data because it is not always plotted correctly. But, he said, in his opinion this data is a little more reliable than NEIC's because the Ensenada Center is closer to Yuma.

The ground continued to rumble throughout the day Tuesday, with a series of quakes ranging from 2.1 to a 4.7, according to preliminary data on the U.S. Geological Survey Web site, earthquake.usgs.gov.

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William Roller can be reached at

wroller@yumasun.com or 539-6858.