Yes, that was a terrific temblor
Several weeks ago, I wrote an article on the earthquake activity across the globe. Since then, other quakes that were higher than a 5.0 magnitude were reported in Indonesia and parts of the South Pacific Islands.
However, the largest earthquake within the last week occurred in Idaho. That one shook Boise and the Treasure Valley shortly before 6 p.m. Mountain time on March 31. The quake measured 6.5 and was felt as far north as Calgary.
According to data from the U.S. Geological Survey, on Oct. 28, 1983, a 6.9 earthquake, the strongest in Idaho’s recorded history, hit near Challis and caused widespread damage. Strong earthquakes are not common in Idaho, but on April 23, 2015, a series of small earthquakes shook the Sandpoint area that were also felt in Coeur d’Alene and other areas. The following morning, April 24, a 6.1 quake was reported off the coast of British Columbia.
In 2001, Spokane was in the throes of an “earthquake swarm.” Nearly 100 earthquakes were recorded over a six-month period with a 3.7 magnitude reported on June 25, 2001. Scientists are still uncertain why our region experienced this swarm of quakes.
There are many fault systems in the U.S., especially in the western sections. Faults are cracks in the earth and movement over time will often create stress along these areas. When the stress becomes too great, the rocks break and then we get the earthquake.
Scientists say the recent Idaho earthquake is not related to the supervolcano at Yellowstone National Park in Wyoming. I’ve read a number of articles that suggest an eruption may be on the horizon. However, volcanologists, geologists and other scientists continue to insist that a massive explosion is not likely to occur at least thousands of years.
Yellowstone goes through cycles of its own. For example, in an article in Newsweek, the Yellowstone supervolcano started to rise at a high rate of nearly 6 inches per year from 2013 to 2015. The unusual activity, according to scientists, was a period of ground deformation resulting from a deep intrusion of magma, which essentially shoves the rocks up above the magma. Some say that the volcano is “breathing,” so there is no concern of an impending eruption.
Yellowstone will go through periods of high activity with earthquake swarms and increased geyser eruptions. According to the U.S. Geological Survey, Steamboat Geyser erupted 47 times in 2019, which was the most in recorded history. By contrast, this geyser was quiet between 1911 and 1961.
Obviously, the most famous attraction at this park are the periodic eruptions of the Old Faithful geyser. As the magma shifts underneath the park, the times of Old Faithful are now more variable. The infamous geyser erupts about every 60 to 110 minutes and the park rangers estimate the time of each eruption, give or take 10 minutes. Back in 2016, I watched the eruption of Old Faithful, which was a majestic wonder to see.
There have been over 137,000 recorded eruptions, but the park rangers say that Old Faithful will one day be no more thanks to the underground shifting of magma. However, they expect another geyser to eventually take its place. The big question we asked is when this may happen, but no one knows for certain.
However, it’s quite likely that one day in the far distant future, there will be a massive explosion. When it occurs, it’s estimated that everything within about 100 miles of Yellowstone would literally be overwhelmed from the effects of the blast. There would be so much dust and ash poured into the upper atmosphere that the Earth would likely go into a “nuclear winter” and ash fallout would be devastating to U.S. crops.
The last time there was a major blast of the Yellowstone volcanic crater, or caldera, was approximately 640,000 years ago and is estimated to be about 2,500 times bigger than the eruption of Mount St. Helens back in 1980. There was also a smaller eruption about 70,000 years ago. Scientists believe that if a major eruption was imminent, there would be large indicators of this event, such as strong earthquake swarms and rapid ground deformation. Currently, the Yellowstone Volcano averages about 1,000 to 3,000 earthquakes per year due to the shifting magma and there are over 10,000 thermal features in this region.
In terms of our local weather, it’s been a crazy year weather-wise across North Idaho and the rest of the Inland Northwest. We got record snows in September and October and above-normal snowfalls in late March and early April. With the exception of the stretch from Jan. 5-18, the rest of the winter had very little snow.
It looks like we’ll have the chance of more wet weather, including some snow in the lower elevations during the upcoming full moon cycle starting on Tuesday. After the middle of the month, Cliff and I think that most of the snow that does fall will be over the mountains. Precipitation this month should be above normal and we’ll end up close to the normal of 70 inches of snow for the season in Coeur d’Alene. Conditions should start turning drier in our region later in May.
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Contact Randy Mann at randy@longrangeweather.com