It is veneered by Quaternary alluvium, loess, glacial outwash, and lacustrine deposits. The consequent surface glacial deposits include gravels as outwash and moraines. Glacial moraines, outwash plains, deltas, lacustrine deposits, and old shorelines are common. They deposited reddish sands and gravels westward and southward in outwash plains. The underlying soil is generally loamy and includes gravelly sand in the glacial outwash. Depositional forms such as terminal moraines and outwash fans are found at their terminal end. Valley trains are long, narrow accumulation of glacial outwash, confined by valley walls. The upper Cedar River flows through a region of deep and porous glacial outwash. The park lies on an outwash plain formed from the outwash of Glacial Lake Grantsburg. Abrasion also produces rock flour which is visible in glacial outwash plains across New England. Glacial outwash (sand and gravel) also occur in small patches, including along Grimshaw Brook. The majority of the New York soils were formed from glacial till and outwash deposits. West of Quelccaya lies a high plain that is formed by glacial outwash and till. If buried they may be partially or totally filled with glacial outwash or other debris. The material of the outwash plans is glacial till.