MAMMOTH LAKES — A swarm of earthquakes -- one a magnitude 5.5 -- jolted a remote, sparsely populated area along the eastern Sierra Nevada on Saturday, authorities said.
A Mono County sheriff's dispatcher said there were no immediate reports of injuries or damage from the temblors centered along the California-Nevada line about 30 miles northeast of Mammoth Lakes.
David Oppenheimer, a seismologist for the U.S. Geological Survey in Menlo Park, said most of the 70 quakes in the sequence that began shortly after midnight Friday were magnitude 2 or less.
The quakes are not surprising because the eastern Sierra has been a seismically active area. Major temblors also have rocked Mammoth Lakes and Bishop.
"For whatever reasons this fault seems to make a lot of noise," Oppenheimer said. "It pops off every once in a while."
The Great Basin that covers most of Nevada and Utah is pulling apart, causing the quakes, he said.