1. Plucking: This occurs when meltwater seeps into cracks and crevices in bedrock. As the water freezes, it expands and exerts pressure on the rock, eventually breaking it apart. The glacier then carries away these broken pieces of rock.

2. Abrasion: This is the process of glaciers grinding and scraping against the bedrock, much like sandpaper. The glacier's weight and movement cause the embedded rocks and sediment within its ice to act as tools, carving out grooves, scratches, and polished surfaces.