Terminal and Recessional Moraines

The Little Ice Age moraine (late 1800s) of Schoolroom Glacier (Grand Teton National Park, WY)
A view of the Little Ice Age moraine (deposited in the late 1800s) of Schoolroom Glacier in Grand Teton National Park (Wyoming) from the modern ice terminus. The moraine dams water melting off the ice today, creating a picturesque turquoise lake that greets hikers as they come over Hurricane Pass.

NPS Photo/Reba McCracken

Terminal and recessional moraines mark the farthest reaches of a glacier—its terminus—at a given point in time. They are usually built from rocks and debris that are transported to the glacier toe in the ice and melt out there.

If the glacier terminus stays in one position for a long time, more debris will accumulate there, building a larger moraine. As long as the glacier does not readvance, the moraine can be preserved for thousands of years!

If, on the other hand, a glacier retreats more quickly, and its terminal position changes every few years, it may leave a series of smaller recessional moraines, rather than a large terminal moraine.

An old terminal moraine on the Clemets Glacier (Glacier National Park, MT)
An old terminal moraine on the Clemets Glacier (Glacier National Park, Montana) reveals how much bigger the glacier used to be.

NPS Photo/Jacob W. Frank

To learn more about glaciers, glacier features, and glacial landforms, see the Glaciers & Glacial Landforms Page.

Part of a series of articles titled Glacier Landforms.

Last updated: February 22, 2018