Terminal moraine
Also called: End moraine · Topic: Landforms and their Evolution: Rivers, Groundwater, Glaciers, Waves and Wind · NCERT: Class 11, Ch 6 "Landforms and their Evolution"
Meaning
A terminal moraine, also called an end moraine, is a long ridge of glacial till across a valley at the snout (end) of a glacier. The ice keeps carrying debris forward and dumping it where the ice melts at its front. If the snout stays in one place for a long time, this debris piles up into a ridge. So a terminal moraine marks the farthest point the glacier ever reached. It may join the lateral moraines on each side in a horseshoe shape. Terminal moraines often dam lakes behind them.
Example
Long Island in New York, USA, is largely built on terminal moraines. An ice sheet left them at its farthest advance during the last Ice Age.
Don't confuse with
- Lateral moraine: a lateral moraine runs along the sides of the valley. A terminal moraine lies across the valley at the glacier's end.