How do recessional moraines show that a glacier paused or briefly advanced during retreat?

A recessional moraine is a type of end moraine that forms when a glacier pauses during its overall retreat.12

These landforms serve as physical markers of a glacier's history because they indicate that the glacier's margin remained in a relatively constant position for an extended period. During such a standstill, the glacier continues to transport and deposit rock debris—known as till—at its snout, allowing for the accumulation of a distinct, ridgelike deposit.12

If a glacier experiences a brief readvance, it may also "bulldoze" existing loose material into a ridge, further contributing to the formation of these moraines. Because these features are left behind as the ice continues to recede, they provide a chronological record of the glacier's movement; in some valleys, researchers can identify 10 or more of these moraines, which help scientists reconstruct the timeline of glacial retreat.21