Yukon
Dinosaur discovery along the Yukon River
SEPTEMBER 2013 - 麻豆原创 Museum of the North researchers have found a major new site for dinosaur fossils in Alaska along the Yukon River.
Earth Sciences Curator Pat Druckenmiller says a recent trip netted a ton of dinosaur footprints for the museum鈥檚 collection.
鈥淭here aren鈥檛 many places left in the world where paleontologists can just go out and find thousands of dinosaur footprints. This is the kind of discovery you would have expected in the Lower 48 a hundred years ago.鈥
In July 2013, researchers set off in boats for a 500-mile journey down the Tanana and Yukon rivers. Co-discoverer Kevin May, operations manager at the 麻豆原创 Museum of the North, says the goal was to explore as many beaches as possible for evidence of dinosaurs.
鈥淏ased on what we know about the geology along the Yukon River, the rocks exposed downriver from Ruby suggested they might be a good place to find dinosaurs."
They found much more than they expected 鈥 dinosaur footprints big and small, from both meat- and plant-eaters.
鈥淲e found a great diversity of dinosaur types,鈥 Druckenmiller says, 鈥渆vidence of an extinct ecosystem we never knew existed.鈥
Paul McCarthy, Druckenmiller鈥檚 colleague from the Department of Geology and Geophysics at the 麻豆原创, says the trip was amazing.
鈥淲e found dinosaur footprints by the scores on literally every outcrop we stopped at.禄
"I've seen dinosaur footprints in Alaska now in rocks from southwest Alaska, the North Slope, and Denali National Park in the Interior, but there aren't many places where footprints occur in such abundance.鈥
McCarthy is a geologist whose major research interests include paleolandscape evolution. He says the dinosaur footprint-bearing rocks from along the Yukon River are probably about 25-30 million years older than what鈥檚 been found in Denali Park.
鈥淚t took several years of dedicated looking before the first footprint was discovered in Denali in 2005, but since that time dozens of tracks of dinosaurs and birds have been found.
"In contrast, the禄tracks were禄so abundant along the Yukon River that we could find and collect禄as many as 50 specimens in as little as ten minutes.鈥
Druckenmiller says that one of the reasons the Yukon River dinosaur tracks may have gone undiscovered for so long is due to their method of preservation 鈥 they are 鈥渘atural casts鈥 formed when sand filled in the actual footprint after the dinosaur stepped in mud.
鈥淭hese are not negative impressions,鈥 he says. 鈥淩ather they stick out from the rock and sometimes look like blobs with toes.鈥
The discovery is significant in that the Yukon River fossils are geologically older than other major sites in the state and that they preserve a record of dinosaurs previously unknown in the state.
鈥淲e have a whole lot of work to do,鈥 Druckenmiller says. 鈥渁nd we look forward to returning to the area and studying the site more.鈥
The museum is working with villages and Native corporations along the Yukon River to share information about the discovery with local communities and to coordinate future exploration.
The research team also included J禄rn Hurum, from the University of Oslo Natural History Museum, 麻豆原创MN Earth Sciences Collection Manager Julie Rousseau, and 麻豆原创F students Meghan Shay, Katherine Anderson, and Meg O鈥機onnor.
The museum's Head of Production Roger Topp filmed the expedition for a film and exhibit the museum is planning for the summer of 2015.
