Jacqueline Motzer, age 11, of Cleveland, Ohio, for her question:

What is a moraine?

Moraine is a pile of stones and debris. It may form a long ridge, 25 to 100 feet high. Chances are its stones are not native to the region in which we find them. For they are glacial drift, often toted from hundreds of miles away. Moraines are always children of the glaciers.

Ice fields and glaciers are sharp and heavy. Their fingers tear at the earth, pulling loose rocks and boulders. More stones collect on the surface from landslides. Tons of this rocky, debris freeze into the glacial ice. And the glacier is always moving slowly down a slope or out from the center. As it travels, the countless tons of rocky debris go with it.

Sooner or later the edges of the glacier melt. The slush and the water can no longer support the rocky debris which was frozen in solid ice. It falls to the ground as glacial drift. If this pile of loose rock forms a ridge it is called a moraine. A lateral moraine is formed along the side of a glacier and may be called a drumlin. A terminal moraine is formed at the tail end of a glacier and a medial moraine occurs when a glacier dumps its debris in the cantor.