Quake Prep

When I wrote my book I expected a San Andreas earthquake scenario to be easy to find with all the Hollywood disaster movies. However, official scenario documentation, particularly more current, has been challenging to find. This particular ShakeOut Earthquake Scenario page on the USGS website is dated January 17, 2018, but much of the information is based on a 2008 ShakeOut Scenario. Since most material I read referenced that 2008 ShakeOut, that is what this scenario post is based on. The ShakeOut  The State of California Department of Conservation has a 2008 earthquake scenario that was used for its ShakeOut drill in the event of an earthquake on the San Andreas Fault ( 2008 ShakeOut Scenario ). The scenario projected about 1,800-2,000 deaths, 50-53,000 injuries requiring emergency care, and $191-200 billion in damages. Like other scenarios, this doesn’t include the lasting disruption those damages will cause. And, those numbers are just estimates from the main shock. Additional ...

 There are 119 public school buildings at increased risk of "significant earthquake damage" because they are classified as unreinforced masonry construction (URM) in seismic safety screenings. What's URM? Here's how earthquakes.utah.gov defines URM "A URM building has brick walls with few or no steel reinforcing bars. During an earthquake, URM buildings are more likely than modern structures to collapse, both inward and outward, and crumble on top of people, cars, sidewalks or structures in and around them. URM buildings are typically older structures. In the 1970s, building codes in Utah were updated to outlaw the construction of new URM buildings."  There are 72,126 children who spend at least some of their schooling in those buildings. That's about 12% of the K-12 children in the state. And those 119 don't include other buildings that were classified as "likely URM" or "likely under-reinforced masonry" buildings. The challenge ...

An earthquake scenario for the San Francisco area is one of the scenarios where finding more recent information is difficult. For an actual scenario, the best I could find was from a simulation in 2006. There was also some information from a 2008 ShakeOut Scenario. There are more recent earthquake hazard and risk calculations available, but I have yet to find these risks and hazards incorporated into a full scenario, where costs and losses are calculated for the earthquake. While the details may be a little different, the whole purpose of this, and other scenarios, is to help you start to grasp the magnitude of damage and loss that a large earthquake can cause. And will very likely cause. Remember that California has generally had better earthquake building codes for a longer time than most of the rest of the United States. An earthquake of a much lesser magnitude can have just as much (if not more) damage and losses in an area where the buildings and infrastructure are not as prepared...

 Thank you for taking some time to read my blog. As I'm sure it is with you, life is busy for me.  While it's been several weeks since my last post, I wanted to let you know that I have five posts in the works.  These forthcoming posts are earthquake scenarios for five of the potentially biggest "big ones" projected to strike the contiguous United States. No, these scenarios are not fictional case studies. Nor are they hyped up Hollywood-style disaster stories. These earthquake scenarios are based on projected risks and cost estimations made by state and federal experts. These experts use knowledge and experience from what is known about earthquake risks and hazards, often through historical and similar event references, in an effort to best calculate the potential and expected damage an earthquake or a projected magnitude will cause in an area. It's not if and earthquake strikes but when, how hard, and how might it affect the area.  Some of the scenarios are bas...

 A tsunami is a high sea wave. It can travel hundreds, even thousands, of miles across the ocean. While over deep water, they can be difficult to detect due to their large wavelengths, which can take 20 to 30 minutes for it to cycle and may only have a few feet of height. As the tsunami passes through shallower water, wave shoaling compresses the wave, making it slower and taller. Tsunami wave rises high and quick over steep coastline Tsunamis can be caused by vertical displacement of the seabed due to an earthquake. They can also be caused by a landslide crashing into the water, and that landslide could have been caused by an earthquake. A December 2004 Indian Ocean earthquake of magnitude 9.1–9.3 caused tsunamis along the coasts of the Indian Ocean. The tsunami waves killed 230,000 to 280,000 people, with heights up to 100 feet. The earthquake was the third largest since recording started in 1900, and it caused one of the deadliest disasters in modern history. It was also the lo...

 A fault rupture is a slip and resulting displacement along a fault. When that rupture extends to the earth’s surface, where we can see it, it’s called a surface rupture. These surface fault ruptures can be vertical or horizontal, and can happen in a small location or extend over a larger area. In many earthquake hazards, surface fault ruptures are identified as ground displacement. Not all earthquakes will produce surface ruptures. The biggest problem with surface ruptures is when a building or other structure is over the rupture. California passed the Alquist-Priolo Earthquake Fault Zoning Act in 1972 to mitigate surface ruptures. The Act prevents the construction of human-occupied buildings on the surface of active faults.  Outside of California, many other earthquake hazard locations don’t have statutes regulating development on faults with surface rupture potential. The main reason for the lack of regulations is usually a lack of historical evidence of earthquakes rupturi...