U.S. earthquake history: The 1906 San Francisco earthquake

jdoughertyDisasters, Gallery

What changes do you make when 80 percent of the city is destroyed? How do you plan ahead so this doesn’t happen here? 114 years ago today, at 5:12 a.m., what is understood to be a magnitude 7.9 earthquake struck the coast of northern California. Shaking lasted for 42 seconds and was felt from Oregon to Los Angeles. The earthquake, … Read More

Today’s M4.2 aftershock: Is this normal?

jdoughertyRecent earthquakes

We will continue to update this post with questions and more information. What do we know so far? Utah was shaken again following a magnitude 4.2 aftershock with an epicenter in Magna at 8:56 p.m. Many Utahns are asking if this is normal to have aftershocks almost a month after the main M5.7 earthquake that happened March 18. We received … Read More

Was the March 18, 2020, Magna Earthquake in the Forecast?

Mackenzie CopeGeology, Recent earthquakes

Utah Geological Survey has a 50-year forecast for earthquakes. In 2016, the Working Group on Utah Earthquake Probabilities (WGUEP) published a 50-year forecast for moderate to large earthquakes in the Wasatch Front region. They determined there was a 93% chance of having one or more earthquakes of magnitude 5 or larger in that time period. Given that high probability, the … Read More

U.S. earthquake history: The Great Alaska Quake of 1964

jdoughertyGeology, Preparedness

And why we don’t expect an earthquake of that size in Utah. On Good Friday, March 27, 1964, at 5:36 p.m. local time, the earth began to shake in the subduction zone in the Prince William Sound in Alaska. The U.S. Geological Survey reports that: The earthquake caused rivers, lakes, and other waterways to slosh as far away as the … Read More