What is the term for earth materials that are brought by the action of glaciers?

The term that refers to earth materials transported and deposited by glacial action is glacial till. Glacial till is unsorted material that glaciers push ahead of them, and as they advance or retreat, they can leave behind a mixture of various sizes of sediment, including clay, silt, sand, gravel, and boulders. This process of glaciation results in a heterogeneous mixture that does not exhibit layering, distinguishing it from other sedimentary deposits.

Drift is a broader term that includes all material that has been transported by glaciers, whether it is deposited in a sorted or unsorted manner. While drift can encompass glacial till, it is not specific enough to describe only that particular type of glacial deposit.

Alluvium, in contrast, refers to sediments deposited by running water, typically in riverbeds and floodplains, which is not relevant to glacial processes. Colloidal sediments refer to very small particles that remain suspended in a solution and are not associated with glacial action either. Thus, glacial till is the most accurate term when specifically discussing materials carried and deposited by glaciers.