Data shows ‘geological hazards’ lurk beneath Yellowstone National Park

The revelation of new data has brought to light a network of “geological hazards” beneath part of Yellowstone National Park, according to scientists studying the ground in that area.

With the help of lidar technology — which used a sensor and laser to map the ground beneath dense forests and other foliage — the data shed light on massive prehistoric landslides and earthquakes that have permanently affected one of the world’s most important geological regions, potentially… Be dangerous. United State. The visible scars left by those landslides and earthquakes are also helping scientists understand more about the current risks of living in the surrounding states, which are now home to millions of people.

Advanced geological surface mapping — a process that maps the terrain in an area and can help scientists gauge the risk of earthquakes, volcanic eruptions or landslides likely to occur there — recently gave geologists and geoscientists their clearest view yet of the bare earth in Paradise Valley and along the Corridor. Near the north entrance of Yellowstone Park. Paradise Valley surrounds a stretch of the Yellowstone River in southwestern Montana, just north of the national park.

The land surface in that area is usually obscured by ground-covering vegetation, making it difficult to see and study some important land features. But using lidar technology, scientists have collected a wealth of data suggesting that the terrain in that area is littered with the remnants of past major earthquakes to a previously unknown extent.

Lidar, which stands for “light detection and ranging,” uses a sensor typically mounted on an aircraft to scan large areas of land. It sends pulsed laser beams towards the Earth and collects information about the surface area as these light pulses are reflected from the Earth’s surface and any other object along the sensor’s path. The information collected using lidar technology, combined with airborne GPS and ground control data, was used to build a high-resolution digital model of the bare earth, allowing scientists to physically “remove” the vegetation.

Now a protected area covering about 3,500 square miles, Yellowstone National Park sits atop a volcanic hotspot that has become a huge source of curiosity for geologists, even though the chance of an eruption is “very unlikely in our lifetime.” books Michael Poland, a geophysicist with the US Geological Survey. But he said studying the area is still important, because of the potential for devastating earthquakes and hydrothermal eruptions, which have a much higher chance of occurring in the foreseeable future.

Discoveries made by “peeling back” the dense foliage covering the terrain allow geologists and hazard specialists to “dramatically improve hazard maps by allowing better characterization of the location, geometry, and activity of known faults and landslides,” wrote Jan Javello, a geologist with the geohazards in montana bureau of mines and geology, In Monday’s edition In a weekly column published by the US Geological Survey. The column, called Yellowstone Caldera Records, was written by scientists and collaborators at the Yellowstone Volcano Observatory.

This same method helped them uncover part of the bare ground With active defects Along the edges of Yellowstone in August 2022. After the latest survey, geologists were able to see a detailed network of fault scarps — uneven displacements in the Earth’s surface, where one side of a fault has moved vertically. against the other. These cracks in the ground are caused by earthquakes.

They are extensions of a fault, called the Migrant Fault, that runs more than 33 miles, almost continuously from Tom Miner Creek near the northwest corner of Wyoming to Livingston, Montana, Gavelot said, and scientists consider them evidence that past earthquakes of magnitude 6.5 or More in the area.

The data also revealed fault scarps near Gardiner, Montana, that are likely connected to another fault system, East Gallatin-Reese Creek, that extends into Yellowstone National Park. It also showed several large prehistoric landslides covering the landscape with “exceptional clarity,” according to Gavilo. Some of those prehistoric landslides were so large that their runout extended down the slope for miles and in one bend blocked part of the Yellowstone River, in Yankee Jim Canyon, creating a temporary lake.

The Montana Bureau of Mines and Geology is now updating its statewide fault and landslide database with new information about Paradise Valley and the North Entrance of the Yellowstone Playground.

“These new datasets provide information needed to improve assessments of potentially hazardous faults and landslides for future updates in county and statewide mitigation efforts for Paradise Valley and Northern Yellowstone National Park, and contribute to USGS national seismic hazard maps,” Gavelot said.