Glacier bay landslide
© Mountain Flying Service — Paul Swanstrom
A 4,000-foot-high mountainside collapsed in Glacier Bay National Park June 28, 2016, in a massive landslide that spread debris and raised a dust cloud for miles across Lamplugh Glacier, seen in this photo taken the next day.

A large landslide has changed the landscape of the Brady Icefield in Glacier Bay National Park.

Debris poured down the face of a mountain and onto Lamplugh Glacier around 8:21 a.m. Tuesday, according to the Alaska Earthquake Center. The debris field is at least six and a half miles long. It was spotted a few hours after the landslide by pilot Paul Swanstrom.

"It was quite dramatic and quite large," said Swanstrom, who added that the dust cloud from the slide initially made it difficult to see.

The shaking from the slide was recorded at monitoring stations around the state and in British Colombia, according to the Alaska Earthquake Center.

Landslides are not uncommon in the national park, but Swanstrom said this is one of the largest he had ever seen in his nearly three decades of flying.

"When it's six and a half miles long, a mile or two wide and probably 100 feet thick, it's pretty remarkable," he said.

The landslide sparked the attention of Colin Stark, a scientist at Columbia University's Lamont-Doherty Earth Observatory in New York. Stacy Morford, a spokesperson for the university, said Stark plans to fly to Southeast Alaska Sunday to analyze the slide.

"This kind of landslide is pretty rare," Stark said in an interview with KTVA. "Maybe once or twice a year on this scale, so we're going to fly onto the glacier and take a look at the landslide debris and try to understand how this kind of landslide works, how does it form and why does it travel so far?"

Stark said other scientists from Canada and Germany will join him to study the landslide.