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Photo: R. Schukar. Used with permission.
In the above photo the bedrock of the steep headwall is located behind Grinnell Glacier. On the topographic map, closely-spaced
brown contour lines show the steep headwall of the cirque. Contour lines revealing the topography of the land surface
are brown, while contour lines showing the topography of the glacier surface are blue.
In the photo, rock debris covers the front margin of Grinnell Glacier. A large proglacial lake occupies the foreground of the photo.
In the photo, you are looking toward the southwest. The location the photo was taken from is shown by the camera on the map. Grinnell
Glacier is considerably larger on the map than in the photograph, thus these two images do not match perfectly. The map was published
in 1968, while the photo was taken in 1993. In the intervening 25 years, Grinnell Glacier has retreated significantly. The photo was
taken standing on rock debris, not from on the glacier as implied on the map.
The photo to the right shows another example of a cirque headwall. Again, the bedrock is nearly vertical and a small glacier sits
in the base of the cirque. A proglacial lakes occupies the foreground of the photo.
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