: Five photographs document the glacial grooves found on Kelleys Island as they looked in the 1930s or 1940s. The photographs measure 6" x 3.5" (15.24 x 8.09 cm). The glacial grooves on the north side of Kelleys Island are the largest easily accessible such grooves in the world. They were scoured into solid limestone bedrock about 18,000 years ago by the great ice sheet that covered part of North America. Remaining today is a trough that measures 400-feet long, 35-feet wide, and up to 10-feet deep. The ice, probably hundreds of feet thick, flowed from the north in what is now the Lake Erie basin. The Devonian limestone containing the grooves contains marine fossils that are 350 to 400 million years old. Many other grooves were quarried away during the nineteenth and twentieth centuries. View on Ohio Memory.
: Om3274_6059734_001 Subjects
: Geography and Natural Resources; Rocks; Glaciers; Historic sites--Ohio--Kelleys Island--Pictorial works; Tourism Places
: Kelleys Island (Ohio); Erie County (Ohio)