 It is a subtler topological feature than the better-known Oak Ridges Moraine, primarily because it was formed as an end moraine at the terminus of a glacial ice sheet, instead of between two retreating ice lobes (known as "interlobate").The ice sheet pushed material to form the ridge, which is composed of "Halton Till" sediment, rich in silt and clay.By contrast, the Oak Ridges Moraine is primarily sand and gravel.