More Mysterious Holes Discovered in Mount Baldy Sand Dune in Indiana
By Eric Zerkel
Published: August 18, 2014
It's been more than a year since then 6-year-old Nathan Woessner fell into a mysterious hole in Mount Baldy, a 126-foot-tall sand dune along the shore of Lake Michigan, and scientists still don't know for sure what caused the expanse to form.
Since then, five more holes have been discovered in Mount Baldy, the most recent of which was discovered by a scientist from a team from Indiana University that descended upon the site this week to begin a year long study on the holes' formation, the Chicago Tribune reports.
The scientist was traversing the dune when he felt the ground beneath him give way, leading to the discovery of a hole "a small child could easily fall into." Todd A. Thompson, who literally stumbled upon the hole, told the Chicago Tribune that an outer layer of sand covered up the opening, hiding the hole from plain view.
Scientists like Thompson believe the key to the holes' formation lies in the mercurial nature of the sand dune. As the National Park Service points out, Mount Baldy is extremely active, shifting on average four feet a year due to gusting winds. In the last 70 years, Mount Baldy has slowly moved inland, to the tune of some 395 feet, the South Bend Tribune points out.
As the dune moves, its sand swallows up anything in its path, including trees and even buildings.
“There were trees growing, there were houses built, and now they’ve been covered by the dune,” Bill Mohaghan, of the Indiana Geological Survey told the South Bend Tribune. “So now the whole shape of the old Mount Baldy from the 1930s is gone, and it’s a different dune.”
Indiana University geologist Erin Argyilan told CBS Chicago that a series of outside factors cause the objects buried beneath the dune to become unsettled, causing collapses like the one that Woessner plunged into.
“There’s been so much disturbance at the lakefront. We have a harbor structure at Michigan City that blocks the natural transport of sand to Mt. Baldy, so the system is what we call sand-starved, and when that happens, plus high visitor activity – people running up and down the dune – what you do is you destabilize the vegetation and trees that were here, and the sand begins to move and migrate,” Argyilan said.
So far, scientists from the Environmental Protection Agency (EPA) and the Indiana University Geological Survey have identified six unstable areas, including a 263-foot by 98.75-foot area where most of the collapses have occurred, the South Bend Tribune notes.
The initial findings of the team's study are set to be published in around six months. In the meantime, Mount Baldy remains closed to the public indefinitely due to safety concerns.
"We want to let the science do the talking before we make any management decisions," Bruce Rowe, spokesman for the Indiana Dunes National Lakeshore, told the Chicago Tribune. "We want to make sure we understand what's happening from a geological standpoint so we can make the proper decision as to what to do with Mount Baldy."