to register for the Great WA ShakeOut – an annual October event – and access helpful resources for participating.
Earthquakes are described as the sudden release of energy occurring from the collision of crustal plates on the earth’s surface, or from the fracture of stressed rock formations in that crust. Though it can be said that there are many technical differences in the rocking, rolling, jarring and jolting felt during an earthquake, they can be devastatingly damaging and seriously unnerving.
Puget Sound is geographically located in an area known as the Pacific Ring of Fire, a distinctive zone marked by the prevalence of earthquake and volcanic activity.Additionally, Washington State is framed by the Pacific, North American, and Juan de Fuca plates, which are segments of the earth’s crust. A significant number of active fault lines or cracks in the crust have been identified in the central Puget Sound area including Seattle and King County.
On an annual basis, thousands of minor earthquake events occur in the greater Puget Sound region. Most of these earthquakes go unnoticed by local residents since it usually requires a magnitude of 2.5 to 3.0 for a local trembler to be noticed.Puget Sound has a long history of documented earthquake activity. The most recent significant activity was the Nisqually Earthquake of February 28, 2001. This earthquake, 10 miles northeast of Olympia in Thurston County (over 40 miles from Seattle), resulted in statewide losses exceeding $1 billion and injured 700 people. Events like the Nisqually seem to reoccur about every 30 to 35 years, while events like the 1949 7.1 magnitude Olympia earthquake occur about once every 100 years. However, subduction earthquakes, events that occur along the interface between tectonic plates, can be spaced anywhere from 100 to 1,100 years apart, although the last recorded subduction event in Washington State occurred in 1700. These great magnitude events can reach 8.0 to 9.0 on the Richter scale.
You can view a map of recent earthquakes at the Pacific Northwest Seismic Network.
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What to do to prepare for an earthquake
- Counties and most Cities have completed a vulnerability analysis. This document may include maps of liquefaction areas. Check the web site for your local office of emergency management.
- Pick safe places in your home where you could drop, cover and hold during an earthquake. Safe places could be under a sturdy table, desk or against an interior wall away from windows, bookcases, or tall furniture that could fall on you. Remember to do the same at work.
- Practice drop, cover and hold. If you physically practice you’ll have a better chance of remembering what to do during a real earthquake.
- Have a fire extinguisher available and know when and how to use it. Minimum recommended size: 2A:10BC.
- If your home was built before 1977, check to see if the frame is bolted to the foundation.
- Prepare for the possibility of tsunamis, power outages and landslides.
What to do during an earthquake:
- During an earthquake, drop, cover and hold where you are until the shaking stops.
- If you are inside, stay inside and wait until the shaking stops and you are sure it’s safe to exit. If you’re in a multiple-story building and you must leave, wait until the shaking stops and use the stairs, do not use the elevator, which can be damaged during an earthquake.
- If in bed – stay in bed and hold on, protecting your head with a pillow.
- When outdoors – find a clear spot away from buildings, trees, and power lines. Crouch down low and cover your head.
- In a vehicle – slow down and drive to a clear space away from overpasses, power lines, buildings, and trees. Stay in your vehicle, with the seatbelt fastened, until the shaking stops. Once the shaking stops, proceed with caution. Avoid bridges or ramps that may have been damaged.
What to do after an earthquake:
- Check yourself. Are you OK and safe?
- Check your family
- If you are near the water, move to high ground immediately as a tsunami could be on its way. Stay there until officials announce it is safe to return.
- Check your home (for fire or electrical problems or gas leak). Control utilities as needed.
- Check your neighbors or co-workers
- Help those who need help!