Sand stalagmites form on the shore of Lake Michigan. Image: David Marvin.
By Marie Orttenburger
Warmer temperatures in the region have melted some of the ice on the Lake Michigan lakeshore.
The conditions this past weekend were just right to showcase a neat phenomenon–the formation of sand stalagmites under a melting layer of ice. Photographer David Marvin, of Lansing, Michigan, caught it on camera during a visit to Michigan’s Sleeping Bear Dunes National Lakeshore.
A portion of the ice on the shore is mixed with beach sand. As it melts, the continuous dripping creates sand stacks that look not unlike something you’d find in Mammoth Cave National Park–on a much smaller scale, of course.
“These fragile stacks of sand are a much-accelerated representation of how stalagmites form in caves through the persistent dripping of mineral-laden water,” Marvin said.
He created a video illustrating the process.
The stalagmites Marvin found measured between 1 and 6 inches tall. Being made only of sand, the fragile structures are doomed to a short existence.
“These stalagmites will not survive much past the melting of the ice shelves that cover and shelter them from the elements,” Marvin said.
But the beach will look a little cooler while they hang around.