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How is till different from glacial outwash?

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esker: Nunavut — glacial landform Eskers, or narrow ridges of gravel and sand left by a retreating glacier, wind through western Nunavut, Canada, near the Thelon River.

The primary difference between till and glacial outwash lies in how they are deposited and their resulting physical characteristics.

Till is unsorted material deposited directly by glacial ice without the influence of running water. Because it is laid down by ice, it shows no stratification and consists of a chaotic mixture of clay, sand, and boulders. The rock fragments in till are typically angular, sharp, and often bear striations or facets from being ground against the glacier bed.12

Outwash, by contrast, is deposited by meltwater streams flowing from a glacier. This process results in stratified (layered) deposits that are sorted by grain size. As the water velocity decreases with distance from the glacier, larger materials are dropped first, while finer sediments are carried further away. Unlike the angular fragments found in till, the gravels and boulders in outwash are generally rounded because their sharp edges are worn away during transport by water.32

Together, these materials form what is known as glacial drift.2