Glacial Deposition
Melting glaciers leave behind a landscape full of glacial deposits. The material from which most of these deposits are created is called till, which is a mixture of different-sized rock particles. In parts of the northern United States, the deposits provide clues to the land's glacial history. Inferring Explain why erratics are often composed of a different type of rock than the surrounding bedrock.
Kettle lake
As a glacier retreats, large blocks of glacial ice become buried in till and other deposits, where they slowly melt, forming pits in the outwash plain. Water often fills these bowl-shaped depressions, creating kettle lakes.