New USGS Fact Sheet About Landslides Delivering Slope Material to Nearshore Waters on California's Big Sur Coast

Landslides are common along the rugged Big Sur coast in central California, where they frequently damage the popular Coast Highway and may impact nearshore marine life. To assist State and Federal agencies in managing this coastline, U.S. Geological Survey (USGS) scientists Cheryl Hapke and Krystal Green have been studying the rates at which material erodes from Big Sur slopes and enters the waters of the adjacent Monterey Bay National Marine Sanctuary. They recently published "Rates of Landsliding and Cliff Retreat Along the Big Sur Coast, California—Measuring a Crucial Baseline" (USGS Fact Sheet 2004-3099), which describes some of their work. Using computer analyses of aerial photographs taken over three short time intervals between 1976 and 2001, the scientists calculated vertical changes in topography, "material-loss rate," within specific landslides over time. Their results indicate wide variations in net loss rates along the coast, with higher loss rates in areas of weaker rocks and during periods of higher rainfall. Their studies of sediment erosion and deposition along the Big Sur coast—conducted in cooperation with the California Department of Transportation (Caltrans), the Monterey Bay National Marine Sanctuary, and the University of California, Santa Cruz—will help State and Federal agencies design coastal-management plans to minimize the environmental impacts of landslides and highway maintenance, while preserving the beauty and protecting the natural resources of this evolving coastline. The new Fact Sheet is available online at URL http://pubs.usgs.gov/fs/2004/3099/.