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Earthquake Damage Explained: The What-If Scenarios

State scientists predict there is a 99.7 percent chance that a magnitude 6.7 or larger earthquake will strike the Bay Area in the next 30 years. But how bad is that? Are we talking about another Haiti or Japan?

We took those questions to a geology professor at Santa Cruz and a researcher at the Northern California USGS to find out what kind of damage different earthquakes could do.

We're not fortune tellers, so we can't tell you exactly what would happen in the event of a 6.7, or an 8.1, or any magnitude for that matter. How old a building is and what it's made of play a big part in the equation. But, we can predict some basic things that might happen depending on where you are.

Click on the cells in the grid below to find out what might happen.

  •  
  • Likely Damage

  • Additional damage in a liquefaction zone

  • What if you're in a landslide zone?

  • And what if you're near the fault line?

  • 0 – 2.9

    About 1,300,000 earthquakes in the world every year.

  • Likely 0-2.9
  • Liquifaction 0-2.9
  • Landslide 0-2.9
  • Fault line 0-2.9
  • 3.0 – 3.9

    About 1,300,000 earthquakes around the world every year.

  • Likely 3.0-3.9
  • Liquifaction 3.0-3.9
  • Landslide 3.0-3.9
  • Fault line 3.0-3.9
  • 4.0 – 4.9

    About 130,000 earthquakes around the world every year.

  • Likely 4.0-4.9
  • Liquifaction 4.0-4.9
  • Landslide 4.0-4.9
  • Fault line 4.0-4.9
  • 5.0 – 5.9

    About 13,000 earthquakes around the world every year.

  • Likely 5.0-5.9
  • Liquifaction 5.0-5.9
  • Landslide 5.0-5.9
  • Fault line 5.0-5.9
  • 6.0 – 6.4

    2011, Christchurch, New Zealand; 6.1M, 1933 Long Beach 6.3M

  • Likely 6.0-6.4
  • Liquifaction 6.0-6.4
  • Landslide 6.0-6.4
  • Fault line 6.0-6.4
  • 6.5 – 6.9

    1989, Loma Prieta, California, 6.9M

  • Likely 6.5-6.9
  • Liquifaction 6.5-6.9
  • Landslide 6.5-6.9
  • Fault line 6.5-6.9
  • 7.0 – 7.9

    2010, Haiti 7.0M; 2008, Shichuan, China ; 7.9M; 1906, San Francisco 7.8M

  • Likely 7.0-7.9
  • Liquifaction 7.0-7.9
  • Landslide 7.0-7.9
  • Fault line 7.0-7.9
  • 8.0 – 8.9

    2010, Offshore Chile 8.8M

  • Likely 8.0-8.9
  • Liquifaction 8.0-8.9
  • Landslide 8.0-8.9
  • Fault line 8.0-8.9
  • 9.0 – 9.9

    2011 Japan 9.0M; 1964, Alaska 9.4M

  • Likely 9.0-9.5
  • Liquifaction 9.0-9.5
  • Landslide 9.0-9.5
  • Fault line 9.0-9.9

Defintions:

  • A liquefaction zone is an area with softer soil, where landfill has been used to build the area, or something that was once a beach or river.
  • A landslide zone is where the earth could fall and damage structures nearby.
  • A fault zone is an area within 50 feet of a fault line. (Note: The Alquist-Priolo Earthquake Fault Zoning Act, restricts construction on or near earthquake faults. High-occupancy buildings, such as schools, hospitals and commercial projects, built since 1972 must be set back 50 feet from an active fault, however California Watch and KQED have found buildings such as schools in those areas.)

Sources:

  1. Thorne Lay, Earth Science Professor, UC Santa Cruz
  2. Tom Holzer, Northern California USGS Geologist
  3. Modified Mercalli Intensity Scale of Shaking Intensity