Movement
Rock glaciers move downslope by deformation of the ice contained within them, causing their surface to resemble those of glaciers. Some rock glaciers can reach lengths of 3 km and can have terminal embankments of 60 m high. Blocks on the surface can be up to 8 m in diameter. Flow features on the surface of rock glaciers may develop from:
- Deformation of the ice core.
- Movement of the debris cover along the debris-ice interface.
- Deformation from a period of glacial advance.
- Changes in the hydrologic balance.
Their growth and formation is subject to some debate, with three main theories:
- A permafrost origin, which implies that the features are related to permafrost action rather than glacial action;
- A mass wasting or landslide origin which does not require the presence of ice and suggests a sudden catastrophic origin with little subsequent movement.
Rock glaciers may move or creep at a very slow rate in part dependent on the amount of ice present.
Read more about this topic: Rock Glacier
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—bell hooks (b. c. 1955)
“She had to lean away.
She dared not stir a foot,
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—Robert Frost (1874–1963)
“So close is the bond between man and woman that you can not raise one without lifting the other. The world can not move ahead without woman’s sharing in the movement, and to help give a right impetus to that movement is woman’s highest privilege.”
—Frances Ellen Watkins Harper (1825–1911)