As the glacier melts, the water carries fine material which is eventually deposited. All of the material moved by the glacial melt water is called glacial drift or glacial till. Glacial outwash is the sand and gravel deposited by the running melt water leaving the glacier. The material is sorted. The heavier particles of sand and gravel are deposited in the glaciated valley. The lighter, finer particles such as clay, are deposited further away from the glacier and are deposited in the outwash plain.