260 earthquakes strike Southeast Idaho since Sept. 2; swarm likely to continue

260 earthquakes strike Southeast Idaho since Sept. 2; swarm likely to continue


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SODA SPRINGS, Idaho — The U.S. Geological Survey reports that the earthquake swarm that's been shaking Southeast Idaho since Sept. 2 is closing in on the 300 quake mark.

As of Sunday evening, the USGS was reporting that there had been 260 quakes during the swarm, including 37 thus far on Sunday.

The USGS' quake numbers are higher than what's being reported by the University of Utah Seismograph Stations.

The university reported that 36 quakes have occurred thus far on Sunday and 206 since the swarm began on Sept. 2.

All of the quakes reported by USGS and University of Utah are occurring in the Caribou County area to the east, southeast and northeast of Soda Springs. The quakes have been felt throughout Southeast Idaho and in Logan, Ogden and Salt Lake City in northern Utah.

Earthquake experts said the USGS and University of Utah use their own networks of seismograph stations to keep track of quakes and that's why their numbers differ. Some local earthquake experts say the University of Utah's numbers are more reliable.

The biggest disparity was during the first three days of the swarm — Sept. 2 to 4, when USGS reported that 45 quakes occurred each of those days for a three-day total of 135 quakes compared to the three-day temblor total of 96 from the University of Utah.

USGS reported that there were 23 quakes this past Tuesday, compared to the 20 reported by University of Utah, 29 on Wednesday compared to the university's 25, and a combined 17 Thursday and Friday compared to the university's 10.

Both USGS and University of Utah reported the same number of quakes on Saturday — 19.

Earthquake experts said the swarm will likely continue for another week but it could continue for even longer. The swarm doesn't necessarily mean a larger much more destructive quake could happen in Southeast Idaho, but there is a slim chance of such a scenario occurring, earthquake experts say.

Both USGS and University of Utah reported that the most powerful quake in the swarm was a 5.3 magnitude temblor that occurred at 5:56 p.m. on Sept. 2. It's been years since Southeast Idaho has experienced a 5.0 or greater magnitude quake. Such temblors can cause damage to buildings.

Authorities have not reported any damage to structures or injuries to people as a result of any of the recent quakes.

Authorities said that Southeast Idaho has never experienced so many quakes in such a short time frame, though the region does experience some seismic activity especially in the Caribou County area.

Below is advice from the U.S. Department of Homeland Security via www.ready.gov/earthquakes on what to do if an earthquake hits your community:

Before an earthquake

  • Before an earthquake occurs, secure items that could fall or move and cause injuries or damage (e.g., bookshelves, mirrors, light fixtures, televisions, computers, hot water heaters.
  • Move beds away from windows and secure any hanging items over beds, couches, cribs or other places people sit or lie.
  • Practice how to “Drop, Cover, and Hold On!”: Plan and practice how to Drop to the ground, Cover your head and neck with your arms, and if a safer place is nearby that you can get to without exposing yourself to flying debris, crawl to it and Hold On to maintain cover.
  • To react quickly you must practice often. You may only have seconds to protect yourself in an earthquake.
  • Store critical supplies (e.g., water, medication) and documents. Plan how you will communicate with family members, including multiple methods by making a
  • family emergency communication plan.
  • Consult a structural engineer to evaluate your home and ask about updates to strengthen areas that would be weak during an earthquake.When choosing your home or business to rent or buy, check if the building is earthquake resistant per local building codes.

During an earthquake

If you are inside a building:

  • Drop down onto your hands and knees so the earthquake doesn’t knock you down. Drop to the ground (before the earthquake drops you!)
  • Cover your head and neck with your arms to protect yourself from falling debris.
  • If you are in danger from falling objects, and you can move safely, crawl for additional cover under a sturdy desk or table.
  • If no sturdy shelter is nearby, crawl away from windows, next to an interior wall.Stay away from glass, windows, outside doors and walls, and anything that could fall, such as light fixtures or furniture.
  • Hold on to any sturdy covering so you can move with it until the shaking stops.
  • Stay where you are until the shaking stops. Do not run outside. Do not get in a doorway as this does not provide protection from falling or flying objects, and you may not be able to remain standing.

If getting safely to the floor to take cover won’t be possible:

  • If getting safely to the floor will be difficult, actions before an earthquake to secure or remove items that can fall or become projectiles should be a priority to create spaces..
  • Identify an away from windows and objects that could fall on you. The Earthquake Country Alliance advises getting as low as possible to the floor. People who use wheelchairs or other mobility devices should lock their wheels, bend over, and remain seated until the shaking stops. Protect your head and neck with your arms, a pillow, a book, or whatever is available.

If you are in bed when you feel the shaking:

  • If you are in bed: Stay there and Cover your head and neck with a pillow. At night, hazards and debris are difficult to see and avoid; attempts to move in the dark result in more injuries than remaining in bed.

If you are outside when you feel the shaking:

  • If you are outdoors when the shaking starts, move away from buildings, streetlights, and utility wires. Once in the open, “Drop, Cover, and Hold On.” Stay there until the shaking stops.

If you are in a moving vehicle when you feel the shaking:

  • It is difficult to control a vehicle during the shaking. If you are in a moving vehicle, stop as quickly and safely as possible and stay in the vehicle. Avoid stopping near or under buildings, trees, overpasses, and utility wires. Proceed cautiously once the earthquake has stopped. Avoid roads, bridges, or ramps that the earthquake may have damaged.

After an earthquake

  • When the shaking stops, look around. If the building is damaged and there is a clear path to safety, leave the building and go to an open space away from damaged areas.
  • If you are trapped, do not move about or kick up dust.
  • If you have a cell phone with you, use it to call or text for help.
  • Tap on a pipe or wall or use a whistle, if you have one, so that rescuers can locate you.
  • Once safe, monitor local news reports via battery operated radio, TV, social media, and cell phone text alerts for emergency information and instructions.
  • Check for injuries and provide assistance if you have training. Assist with rescues if you can do so safely.
  • If you are near the coast, learn about tsunamis in your area. If you are in an area that may have tsunamis, when the shaking stops, walk inland and to higher ground immediately. Monitor official reports for more information on the area’s tsunami evacuation plans.
  • Use extreme caution during post-disaster clean-up of buildings and around debris. Do not attempt to remove heavy debris by yourself. Wear protective clothing, including a long-sleeved shirt, long pants, work gloves, and sturdy, thick-soled shoes during clean-up.
  • Be prepared to “Drop, Cover, and Hold on” in the likely event of aftershocks.

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