A geologic event that no one saw nevertheless captivated readers this year – a debris flow on Mount Baker’s eastern flank that was photographed by climbers in early June.
Such debris flows occur occasionally and are not a concern to anyone except mountaineers, said Western Washington University geologist Dave Tucker. But observers could see a dark gray streak on the 10,781-foot active volcano that’s about 30 miles east of Bellingham.
“It’s not a threat, it’s a scientific curiosity, and it will be very visible,” said Tucker, research associate in WWU’s Geology Department and a board member of the Mount Baker Volcano Research Center.
A debris flow is like an avalanche that scours the mountainside, gathering ice and rock and volcanic deposits in a mad downhill rush of material that’s the consistency of wet concrete. They can be deadly.
“They happen every three, four, five years and some of them are very large,” Tucker said. “If they happen when climbers are on the mountain, it can be a problem.”
Tucker said a debris flow narrowly missed a group of climbers in 2006.
Tucker said the debris flow was reported by Corey Vannoy of Bellingham, who summited with 10 mountaineers in two parties June 4-5, 2016. He emailed images that clearly show the point below Sherman Peak near the crater where snow and ice broke free and traveled downhill.
“It was massive, the size of this debris flow. We almost couldn’t believe it. We were dumbfounded,” said Vannoy, a chemical engineer at the BP refinery near Ferndale. “This is a ridiculous amount of debris.”