The 4.8 magnitude earthquake that shook Yellowstone National Park this weekend was unremarkable besides the fact it happens around every decade or so, a University of Utah professor says.

The temblor, which struck about 4 miles north-northeast of the Norris Geyser Basin at 6:34 a.m. Sunday, wasn’t related to the caldera, University of Utah geophysics professor Bob Smith said. It’s not an indication that the supervolcano is set to explode and result in fiery deaths for millions, the seasonal Moose resident said.

“We’ve had several magnitude 4.8s, 4.9s in the history of Yellowstone,” Smith said.

“What we’re seeing is kind of the upper end of the Richter scale that we see in Yellowstone,” he said. “I think it’s just coincidental.”

It has been considerably longer than usual since such a powerful event occurred. The last Yellowstone quake as large as 4.8 magnitude rumbled on Feb. 22, 1980 — more than 34 years ago.

As a result, Sunday’s earthquake was covered in newspapers around the country. It also grabbed the attention of Yellowstone supervolcano doomsday alarmists.

The Turner Radio Network published a story Sunday warning that the Yellowstone quake may indicate the pending eruption of the “SUPER volcano.”

Shake was outside the caldera

“A total of seven earthquakes have now hit Yellowstone and the pattern is sequential clockwise, around the super volcano caldera!” the Turner radio story said. “It appears the super volcano is “unzipping!”

The caldera is not unzipping, Smith said. In fact the earthquake is outside the bounds of the 55-mile by 18-mile magma chamber.

“It’s really north of the caldera boundary,” Smith said. “So the earthquakes are in a system that’s dominated by faults as opposed to a system that’s dominated by magmatic activity.”

The measurements Smith and colleagues took of the Yellowstone earthquake Sunday, which was one of 31 that day, did not all come in uniform, he said. The U.S. Geological Survey, deemed the authority on the matter, called it a magnitude 4.8.

“We looked at it three different ways,” Smith said.

Different methods, he said, assessed it at magnitudes of 4.3, 4.9 and 5.0.

Yellowstone spokesman Al Nash told the Jackson Hole Daily this weekend that no known human was in the Norris area at the time of the temblor.

Thirty-three people reported having felt the quake, and in places as far away as Big Timber and Belgrade, Mont., according to the USGS’s “Did you feel it?” Web page. One respondent in Jackson Hole who apparently knew of the incident reported having “not felt” the event.

277 quakes recorded in area

“We call it a light earthquake,” Smith said. “It’s very shallow.

“It was caused by a fracture in the ground and the fracture might be a kilometer long,” he said.

Sensors detected 277 earthquakes in and around the Yellowstone in March, a higher than average number, according to a Yellowstone Volcano Observatory monthly report.

The big one is part of a “ground uplift”-related cluster that includes 70 temblors, including four magnitude 3.0 or higher events. The event is still going on, the report said.

Yellowstone’s largest quake in three decades did not cause any measurable ground deformation, the observatory report said. Over the last eight months, a GPS station in North-Central Yellowstone has moved about 1.5 centimeters east, 2 centimeters north, and 5.5 centimeters upward.

For Smith, it wasn’t surprising that 4.8 magnitude quake has caused such a stir in certain circles.

On Tuesday, talk radio host Alex Jones’ website, InfoWars.Com, posted a Youtube video of a herd of Yellowstone bison galloping down a highway. The title: “Animals fleeing from Yellowstone Supervolcano?”

“These periods of time, when they speculate on something, occur all the time,” Smith said. “Every three months we get inundated.”

“There are a lot of people out there that truly believe the world’s coming to an end,” he said, “and they have an enormous following.”

This article appeared in the Jackson Hole News & Guide on April 2, 2014.