CGS Geologists Assess Multiple Fire Burn Areas for Landslide Potential: 10-1-20 Update

Wildfires are a disaster that can spawn yet another disaster. Fire eliminates ground covering on slopes, exposing the soil underneath and making it more susceptible to debris flows. Such events can be catastrophic, as was the case in Montecito (Santa Barbara County) in 2018. David Longstreth, senior engineering geologist in California Geological Survey’s (CGS) Forest and Watershed Geology program, is one…

The Mammoth Lakes Earthquakes – 40th Anniversary

On May 25, 1980–nearly one week after the spectacular eruption of the Mount St. Helens volcano–at 9:33 a.m. PST, a magnitude 6.0 earthquake rocked through Mammoth Lakes, California. During the next 16 minutes, four more shocks, magnitude 4.1 – 5.5 followed. This seismic activity was the beginning of an earthquake sequence that produced 72 magnitude…