Natural Hazards Mitigation Plan Section 6 – Earthquakes City of Newport Beach, California SECTION 6: EARTHQUAKES Table of Contents Why Are Earthquakes A Threat to the City of Newport Beach? ................ 6-1 Earthquake Basics - Definitions.................................................................................................... 6-3 Causes of Earthquake Damage .................................................................................................... 6-7 Ground Shaking .................................................................................................................................................. 6-7 Liquefaction ......................................................................................................................................................... 6-8 Earthquake-Induced Landslides and Rockfalls .......................................................................................... 6-8 Fault Rupture ...................................................................................................................................................... 6-9 History of Earthquake Events in Southern California .................................... 6-9 Unnamed Earthquake of 1769 .................................................................................................................. 6-11 Unnamed Earthquake of 1800 .................................................................................................................. 6-11 Wrightwood Earthquake of December 12, 1812 ................................................................................ 6-12 Unnamed Earthquake of December 21, 1812 ..................................................................................... 6-12 Unnamed Earthquake of 1855 .................................................................................................................. 6-12 San Jacinto Earthquake of 1899 ............................................................................................................... 6-12 Elsinore Earthquake of 1910 ...................................................................................................................... 6-12 San Jacinto Earthquake of 1918 ............................................................................................................... 6-13 Long Beach Earthquake of 1933 ............................................................................................................... 6-13 Torrance-Gardena Earthquakes of 1941 ................................................................................................ 6-13 San Fernando (Sylmar) Earthquake of 1971 ......................................................................................... 6-14 Oceanside Earthquake of 1986 ................................................................................................................. 6-14 Whittier Narrows Earthquake of 1987 ................................................................................................... 6-14 Newport Beach Earthquake of 1989 ....................................................................................................... 6-15 Landers and Big Bear Earthquakes of 1992 .......................................................................................... 6-15 Northridge Earthquake of 1994 ................................................................................................................ 6-15 Hector Mine Earthquake of 1999 ............................................................................................................ 6-16 Chino Hills Earthquake of 2008 ................................................................................................................ 6-16 Baja California Earthquake of 2010 ......................................................................................................... 6-16 La Habra Earthquake of 2014 .................................................................................................................. 6-17 Earthquake Hazard Assessment .................................................................... 6-17 Choosing Earthquakes for Planning and Design ..................................................................... 6-17 Seismic Shaking .............................................................................................................................. 6-18 Newport-Inglewood Fault Zone .................................................................................................................. 6-21 San Joaquin Hills Fault .................................................................................................................................. 6-22 Compton Thrust Fault ................................................................................................................................... 6-22 Palos Verdes Fault Zone ............................................................................................................................... 6-23 Coronado Bank Fault ..................................................................................................................................... 6-24 Puente Hills Thrust Fault .............................................................................................................................. 6-24 Elsinore – Chino – Whittier Fault Zone ................................................................................................... 6-25 Sierra Madre Fault Zone .............................................................................................................................. 6-26 San Andreas Fault Zone ............................................................................................................................... 6-27 Fault Rupture ................................................................................................................................. 6-29 Liquefaction and Related Ground Failure ................................................................................ 6-32 2014 PAGE 6-i Natural Hazards Mitigation Plan Section 6 – Earthquakes City of Newport Beach, California Lateral Spreading ............................................................................................................................................ 6-33 Flow Failure ....................................................................................................................................................... 6-33 Ground Oscillation .......................................................................................................................................... 6-34 Loss of Bearing Strength ............................................................................................................................... 6-34 Ground Lurching .............................................................................................................................................. 6-34 Seismically Induced Slope Failure ............................................................................................................... 6-34 Ridgetop Fissuring and Shattering .............................................................................................................. 6-35 Vulnerability Assessment ................................................................................ 6-35 Risk Analysis....................................................................................................... 6-38 HazUS Scenario Earthquakes for the Newport Beach Area ............................................... 6-43 Inventory Data Used in the HazUS Loss Estimation Models for Newport Beach ......... 6-45 Estimated Losses Associated with the Earthquake Scenarios ............................................. 6-48 Building Damage ............................................................................................................................................. 6-49 Casualties .......................................................................................................................................................... 6-52 Essential Facility Damage ............................................................................................................................. 6-54 Building-Related Losses ................................................................................................................................. 6-55 Shelter Requirement ...................................................................................................................................... 6-55 Transportation Damage ............................................................................................................................... 6-56 Utility Systems Damage ................................................................................................................................ 6-57 Fire Following Earthquake ............................................................................................................................ 6-58 Debris Generation .......................................................................................................................................... 6-60 Existing Mitigation Activities ........................................................................... 6-60 California Earthquake Mitigation Legislation .......................................................................................... 6-60 City of Newport