Answer
End moraines and ground moraines are both types of moraines formed by sediment deposition by glaciers, but they differ in their location and formation processes.
An end moraine, also known as a terminal moraine, is a ridge of till that marks the furthest advance of a glacier. It forms at the leading edge or terminus of the glacier, where the glacier's meltwater deposits the sediment it carries. End moraines are typically arc-shaped and can be quite large. They represent the farthest extent of glacial advance during a particular phase. The formation of end moraines reflects the balance between the accumulation and ablation processes of the glacier. When the glacier advances, it pushes and deposits sediment to form the end moraine, indicating a positive glacial budget with more accumulation than loss. Conversely, when the glacier retreats, the end moraine is left behind, indicating a negative glacial budget with more loss than accumulation.
In contrast, a ground moraine is a layer of till that covers the land beneath a glacier. It forms as the glacier moves over the landscape, grinding and pulverizing the underlying rock. The debris and sediment produced by this grinding action are deposited as a relatively flat and irregular layer beneath the glacier. Ground moraines can have a vast extent and can be found throughout the area covered by the glacier. Ground moraines are not directly related to the glacial budget but are influenced by the erosive and depositional processes of the glacier as it flows over the land. The thickness and distribution of ground moraines can vary depending on the characteristics of the glacier and the underlying terrain.
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As per text in section 18.4
