Researchers Dig For Answers About How Often Big Earthquakes Hit Tetons

Sep 21, 2017

On Wednesday, the trench was filled back in.
Credit Chris DuRoss USGS

Scientists this week closed up a large trench they built to study the Teton Fault, a 40-mile geological feature along the east side of the Teton Range.

The research team affiliated with the U.S. Geological Survey, the Forest Service, the Jackson Hole Mountain Resort and many other groups will now take data they collected in the trench and try to evaluate how often large earthquakes hit the Teton Fault.

U.S.G.S. Geologist Chris DuRoss said, it’s important information because, with about three million people visiting Grand Teton each year, a ground-cracking earthquake could create a lot of chaos.

“What we know about the fault is that these earthquakes, they occur very infrequently, many thousands of years apart,” DuRoss said. “Although they do occur infrequently, they’re still of concern to us because they can create strong ground shaking in Teton Valley.”

Earlier research shows two such quakes have struck in the last 11,000 years.

DuRoss also said that the Teton Fault and the Yellowstone supervolcano are unrelated.

“The Teton Fault is part of a very different kind of tectonic region than Yellowstone. These are two different systems,” he said. “What we can say is that a large earthquake on the Teton Fault is about one thousand times more likely than an explosive caldera-forming eruption at Yellowstone.”

DuRoss says now that the trench is closed, they’ll spend the next year evaluating their radiocarbon dating, 3-D maps, and other data in hopes of formulating a clearer understanding of just how often big earthquakes strike the region.