What are erratics in a glacial landscape?

Erratics in a glacial landscape refer specifically to large boulders that have been transported by glaciers. These boulders can originate from areas far from where they are found today, as glaciers can carry them over significant distances. When the glacier retreats or melts, these stones are left behind, often sitting on different types of bedrock or sediment, which highlights their journey. Their presence is a clear indicator of past glacial activity, and they often stand out in the landscape due to their size and the difference in composition compared to local rocks.

The other concepts do not accurately describe erratics. Small particles of sediment indicate a different aspect of glacial deposits, while small rocks formed by erosion refer to a different geological process entirely. Flat stones used in construction also do not relate to the phenomenon of glacial transport, emphasizing how erratics serve as a distinctive sign of glacial movement and deposition.