Urban Seismic Hazards

Urban Regions :

California

• Liquefaction Hazard Maps for San Francisco Bay Area

  

  The liquefaction hazard maps for the SF Bay Area, NW Alameda County, and N Santa Clara Valley predict the approximate percentage of each designated area that will have surface manifestations of liquefaction during an M7.1 earthquake on the Hayward fault. An earthquake of this magnitude is expected if the whole Hayward fault ruptures in a single event (Working Group on California Earthquake Probabilities, 1999).

• Soil Type and Shaking Hazard in the San Francisco Bay Area

  

  Soil Type and Shaking Hazard in the S.F. Bay Area. The type of soil at a site affects the intensity of shaking there. Learn about this effect and use interactive maps to look up the soil type at any site in the San Francisco Bay Area.

• Liquefaction Susceptibility Map for San Francisco Bay Region

  

  Shows the distribution of rock and sediment having different vulnerabilities to liquefaction when shaken by earthquakes, together with explanation of the process and examples of its effects.

• Hazard Maps for San Francisco Bay Area

  

  Association of Bay Area Governments offers shaking maps, liquefaction maps, predictive transportation disruption maps, and more.

• Seismic Hazard Maps for California

  

  In 1880 the California Legistlature established the State Mining Bureau which has evolved during its 127 years of continuous service into the modern California Geological Survey (CGS).

Central and Eastern US

• Central U.S. Seismic Velocity Model

  

  The model covers a region of approximately 650,000 km² and includes several urban areas, such as Little Rock, AR; Evansville, IN; Memphis, TN; Nashville, TN; Louisville, KY; and St. Louis, MO.

• Central and Eastern U.S. Hazard and Seismicity Map

  

  This map shows earthquakes (circles) greater than magnitude 3.0 since 1974 plotted on the 2014 USGS National Seismic Hazard Map for the central and eastern United States. Warmer colors on this map indicate areas of higher hazard. Larger earthquakes are represented by larger circles. (PDF)

• Memphis, Shelby County Earthquake Hazards Mapping

  

  Memphis, Shelby County, Tennessee, is located where damaging earthquakes are only moderately likely, but the consequences of earthquakes, mainly from the New Madrid seismic zone, can be very high. This densely populated urban area is built on a 1-kilometer-thick sequence of sediments deposited in a trough known as the Mississippi embayment. This thick pile of sediments significantly affects earthquake ground motions. We, the authors, have generated a suite of seismic hazard maps for a six-quadrangle area in Memphis, Shelby County, Tennessee, that accounts for these effects. These maps and their derivative products represent the collaborative efforts of the U.S. Geological Survey (USGS) and its partners.

• Evansville Area Earthquake Hazards Mapping

  

  In tri-state Evansville area of Indiana, Kentucky, and Illinois the USGS is partnering with a local working group to produce urban earthquake hazard maps for the community.

• St. Louis Area Earthquake Hazards Mapping

  

  In the St. Louis area of Missouri and Illinois the USGS is partnering with a local working group to produce urban earthquake hazard maps for the community.

Pacific Northwest

• Seattle Urban Seismic Hazard Maps

  

  The USGS has produced a new series of earthquake hazard maps for the City of Seattle. These “urban seismic hazard” maps provide a much higher-resolution view of the potential for strong earthquake shaking than previously available. This new view is particularly important for Seattle, which sits atop a sedimentary basin that strongly affects the patterns of earthquake ground shaking and therefore, of potential damage.

• Lifelines and earthquake hazards in the greater Seattle area

  

  A Pacific Northwest Urban Corridor Geologic Mapping Project of the Western Earth Surface Processes Team.

• Pacific Northwest Urban Mapping & Geologic Hazards

  

  The urban corridor lies within the Puget-Willamtte lowland, a seismically active forearc basin overlying the Cascadia subduction zone - Pacific Northwest Urban Corridor Geologic Mapping Project of the Western Earth Surface Processes Team