Giant stair steps
A small glacier located in a cirque; a glacier that does not extend beyond the edge of the cirque; the part of a valley glacier
that lies in the cirque at the head of the glacier.
Photo: H.E. Malde. 1951. USGS Photographic Library, photo mhe00050. <http://libraryphoto.cr.usgs.gov/>Accessed June 2010.
Siyeh Glacier in Glacier National Park, shown in the photo above and on the map to the right, is an example of a cirque glacier; it no longer extends beyond the edge of its cirque.
On topographic maps blue contour lines show the surface topography of glaciers while a dashed blue line shows the border of
glaciers. The red line on the map shows the location of the very top edge of the cirque, while the blue line on the map shows
the approximate extent of the cirque visible in the photograph. North is toward the top on the topographic map; the photo was
taken looking approximately south or south-southwest. Cracker Lake is visible in the lower right corner of the photo. The small
arm of Siyeh Glacier that extends to the northwest on the topographic map is visible to the right on the photograph, as are the
moraine deposits (brown speckles) located in front of the glacier terminus.
The valley currently occupied by Canyon Creek is U-shaped, which indicates that at some time in the past Siyeh glacier was
large enough to extend down the valley currently occupied by Canyon Creek. The moraine deposits (brown speckles) that intersect
the word "Canyon" on the map indicate a former position of the glacier terminus. Even when Siyeh glacier was large
enough to cover this land area it would still have been considered a cirque glacier because it still did not extend beyond the
edge of the cirque.