‘Volcanic unrest’ in Mammoth Lakes: Nearly 3 dozen small quakes in 24 hours

In this 2012 photo, runners take to a trail in the Mammoth Lakes region in California's Eastern Sierra.
In this 2012 photo, runners take to a trail in the Mammoth Lakes region in California’s Eastern Sierra.
(Wally Skalij / Los Angeles Times)

Nearly three dozen earthquakes have rattled the Mammoth Lakes region in less than 24 hours as the area continues to experience ripple effects of “volcanic unrest,” according to the U.S. Geological Survey.

The temblors -- all between magnitude 2.5 and 3.8 -- have struck since 9 a.m. Thursday, with the latest recorded at 1:49 a.m. Friday, according to the USGS. The 3.8-quake occurred at 9:21 p.m. with an epicenter six miles from Mammoth Lakes.

Heightened earthquake and ground uplift activity have been measured at Mammoth Mountain and the Long Valley Caldera over the last few decades.

At 11,053 feet, Mammoth Mountain in California’s Eastern Sierra is a lava dome complex on the southwest rim of Long Valley Caldera, although eruptions haven’t occurred for some 57,000 years. The recent swarm of quakes in and around the mountain is being tied to recent “volcanic unrest” marked by gas emissions, tree die-offs and intrusions of upward-moving sheets of rock, according to the USGS.


It is unclear whether the latest round of quakes is linked to the volcanic unrest, but USGS spokeswoman Susan Garcia said the region is “pretty active.”

Meanwhile, Mammoth Lakes locals are taking it in stride.

Jose Garcia, a clerk at an area Chevron gas station, said the quakes were pretty normal and haven’t set off any alarms.

“It’s not shaking bad,” he said.

Everything was also business as usual at a Mammoth Lakes Vons, employee Albert Branca said.

“Nobody’s really talking about it,” he said.

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