Lobes formed along the ice fornt where it moved relatively quickly. Shelter Island, which is shaped like two chevrons, may have been formed in an interlobate zone. Loess is wind-deposited silt that forms thick deposits along the North Shore on eastern of Long Island. In China, loess is very thick and people can build cities by excavating it because it can hold up wel without collapsing, except when earthquakes occur. When this happens, the result can be disastrous.
Silt can fillin spaces between larger particles in till.
This makes it able to hold moisture much more effectively than sand and gravel, which characterize outwash. Because it strongly influences moisture content, the amount of silt can help explain the vegetation. The Dwarf Pine Plains is a biological response to drought. The moraines contain substantial amounts of pre-advance outwash. The glacier advanced over this pre-advance outwash.