Volcano Update from Archive

Saturday, June 28, 2008 08:16 PDT (Saturday, June 28, 2008 15:16 UTC)

37.70°N 118.87°W, Summit Elevation 11122 ft (3390 m)
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN

A magnitude M=4.3 earthquake at 7:44 AM (PDT) this morning (June 28) was located in the Sierra Nevada just south of Long Valley caldera (2 miles east of Convict Lake, 8 miles WNW of Tom's Place). This earthquake will have produced perceptible shaking throughout the Mammoth Lakes area. As of this update, it has produced only a few, small aftershocks, the largest of which was a M=1.3 earthquake at 8:03 AM.

The Long Valley Observatory (LVO) monitors and studies earthquakes, ground deformation, degassing, and other types of geologic unrest in and around the Long Valley Caldera. The 15 by 30 km Long Valley Caldera was formed during an eruption 760,000 years ago and is located 20 km south of Mono Lake along the east side of the Sierra Nevada in east-central California. There have been multiple smaller eruptions since the caldera-forming eruption with the most recent occurring 250 years ago in Mono Lake at the north end of Mono-Inyo Craters volcanic chain. LVO is one of the five USGS Volcano Observatories that monitor volcanoes within the United States for science and public safety.