A moraine is sediment deposited by a glacier. A ground moraine is a thick layer of sediments left behind by a retreating glacier. An end moraine is a low ridge of sediments deposited at the end of the glacier. It marks the greatest distance the glacier advanced.

Like flowing water, flowing ice erodes the land and deposits the material elsewhere. Glaciers cause erosion in two main ways: plucking and abrasion. Plucking is the process by which rocks and other sediments are picked up by a glacier. They freeze to the bottom of the glacier and are carried away by the flowing ice.

Glaciers erode the underlying rock by abrasion and plucking. With the weight of the ice over them, these rocks can scratch deeply into the underlying bedrock making long, parallel grooves in the bedrock, called glacial striations. Glacial striations point the direction a glacier has gone.

Glaciers erode and transport rock as they flow down slope. Then, when the glaciers start to melt or recede, the sediment is deposited as unsorted glacial till, often in characteristic landforms such as moraines and their associated sedimentary facies.

Glaciers do not sort sediments as flowing water and wind do. Poorly sorted glacial sediments are known as till. At the end of a glacier, where ice is melting as fast as it is being supplied from upstream, the sediments are deposited in a terminal moraine, a ridge of poorly-sorted glacial till.

Rain, rivers, floods, lakes, and the ocean carry away bits of soil and sand and slowly wash away the sediment. Rainfall produces four types of soil erosion: splash erosion, sheet erosion, rill erosion, and gully erosion.

One type, biological weathering , is caused by animals and plants. For example, rabbits and other burrowing animals can burrow into a crack in a rock, making it bigger and splitting the rock. You may have seen weeds growing through cracks in the pavement.