Scientists are stumped as they try to determine exactly why the state of Idaho has been hit with hundreds of low- and medium-level earthquakes since late March.
The most powerful quake struck central Idaho on Saturday, April 12, when a 4.9 magnitude tremor shook walls and knocked objects off the tables. That quake was the strongest to hit the state since 2005, and was followed by another 4.4 magnitude quake on Monday – felt nearly 100 miles away by residents in Montana.
No injuries or damage have been reported, but the increased seismic activity has geologists wondering why the central part of the state has become such a hot spot for earthquakes since March 26. According to Reuters, government scientists are scheduled to use special seismometers to study the phenomenon more closely and hopefully reach some kind of conclusion.
As noted by geologist Bill Phillips of the Idaho Geological Survey, a series of earthquakes like this would normally signal that molten rock is moving along a well-known and active fault in the state – the same one responsible for generating a 6.9 magnitude tremor in 1983 that killed two children.
However, Phillips told Reuters that scientists might need to look for a different explanation in this situation.
"What has many of us scratching our heads is the present-day swarm doesn't appear to be on the big, active fault in the area that ruptured in 1983 and caused the largest earthquake in Idaho," he said.
Although the cause of Idaho’s spike in seismic activity remains unknown, it’s not the only state to experience such a surge. As RT reported earlier this month, Oklahoma has already experienced more earthquakes in the first four months of 2014 than it did the entirety of last year, raising concerns that oil drilling procedures like fracking are to blame.
"We have already crushed last year's record for number of earthquakes," said Austin Holland of the Oklahoma Geological Survey.
Meanwhile, Ohio has also seen increased reports of earthquakes, which geologists have linked to fracking operations – which involve blasting highly pressurized water, sand, and other chemicals into rock in order to free up oil. Since waste is sometimes disposed along fault lines, scientists believe the procedure could instigate earthquakes.
It’s currently unclear if Idaho’s seismic activity is related to oil or gas gad production, though residents have expressed concern over such operations in the past. As geologists continue to investigate the cause, local schools have increased response drills and area officials have requested emergency personnel to be on alert in case anything dangerous were to occur.