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What are lateral moraines and end moraines?

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Map showing the extent of the Laurentide, Cordilleran, and Greenland ice sheets during the Wisconsin glaciation, roughly 100,000 to 11,000 years ago. The Laurentide Ice Sheet covers most of present-day Canada and parts of the northern United States in light blue, the Cordilleran Ice Sheet covers the Pacific Northwest in teal, and the Greenland Ice Sheet is marked in purple. Modern international and state or provincial boundaries are outlined for reference. — Pleistocene Epoch Ice sheets during the Wisconsin glacial episode penetrated deep into North America.

In the context of glacial geomorphology, moraines are accumulations of rock debris, or till, transported and deposited by glaciers. They are categorized based on their location relative to the ice mass:

Lateral moraines are elongate ridges of debris that form along the valley slopes next to the side margins of a glacier. This material is typically derived from the valley walls through processes such as erosion and avalanche, eventually being deposited as the glacier recedes.123
End moraines (also known as terminal moraines when they mark the outermost extent of a glacial advance) are linear accumulations of till that form at the lower end or snout of a glacier. They often appear as ridges of chaotic debris that curve convexly across a valley, created either by material melting out directly from the ice or by the glacier "bulldozing" loose sediment as it advances.123

These landforms were instrumental in early 19th-century scientific observations, which helped researchers identify and interpret the more extensive glaciation that occurred during the Pleistocene Epoch.3