Factors Affecting Landslide-Susceptibility in San Mateo County, California

Research Article| November 01, 1983 Factors Affecting Landslide-Susceptibility in San Mateo County, California RICHARD A. ROTH RICHARD A. ROTH Department of Civil Engineering, Stanford University, Stanford, CA, 94305 * Richard A. Roth, Dames and Moore, 445 South Figueroa St., Suite 3500, Los Angeles, CA 90071. Search for other works by this author on: GSW Google Scholar Author and Article Information RICHARD A. ROTH * Richard A. Roth, Dames and Moore, 445 South Figueroa St., Suite 3500, Los Angeles, CA 90071. Department of Civil Engineering, Stanford University, Stanford, CA, 94305 Publisher: Association of Environmental Factors Affecting Landslide-Susceptibility in San Mateo County, California. Environmental ; xx (4): 353–372. doi: https://doi.org/10.2113/gseegeosci.xx.4.353 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyEnvironmental & Engineering Geoscience Search Advanced Search Abstract A data set was constructed to analyze regional landslide-susceptibility in San Mateo County, California. The data set consists of 2,639 cells spaced at 2,100 ft intervals. Six input variables were used to define the characteristics of each cell. Information was compiled from maps that had been published by others pertaining to slope angle, rock type, rainfall, soil type, vegetation type and the distribution of landslide deposits. A digitizing tablet was used to input and store the data in digital form on a computer.The geologic units were separated into four categories of relative susceptibility on the basis of a statistical analysis of the data: highly susceptible, susceptible, moderately susceptible, and least susceptible. The Purisima Formation, Monterey Shale, Mindego volcanics, San Lorenzo Formation and Tertiary intrusives were designated as highly susceptible.The distribution of landslides was found to be sensitive to slope angle only up to a slope of about 15 percent (9 degrees). Other factors appear to be more significant in controlling landslide distribution at steeper slope angles.Susceptibility to slope failures was found to be directly related to the mean annual rainfall. This can be explained theoretically by the relationship between pore-water pressure and soil shear strength.Soil type and vegetation type were found to be secondary factors in determining the distribution of slope failures. This may reflect the fact that only landslides with long dimension in excess of 500 ft were considered in this study.The methodologies of Brabb and others (1972), and Radbruch and Crowther (1973) used to create regional susceptibility maps were found to be consistent with the statistical analyses performed in this study. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.