Bergschrund
Encyclopedia
Crevasse
A crevasse is a deep crack in an ice sheet rhys glacier . Crevasses form as a result of the movement and resulting stress associated with the sheer stress generated when two semi-rigid pieces above a plastic substrate have different rates of movement...
that forms where the moving glacier ice separates from the stagnant ice above. It is often a serious obstacle for mountaineers
Mountaineering
Mountaineering or mountain climbing is the sport, hobby or profession of hiking, skiing, and climbing mountains. While mountaineering began as attempts to reach the highest point of unclimbed mountains it has branched into specialisations that address different aspects of the mountain and consists...
, who sometimes abbreviate "bergschrund" to "schrund".
In a corrie
Cirque
Cirque may refer to:* Cirque, a geological formation* Makhtesh, an erosional landform found in the Negev desert of Israel and Sinai of Egypt*Cirque , an album by Biosphere* Cirque Corporation, a company that makes touchpads...
or cirque
Cirque
Cirque may refer to:* Cirque, a geological formation* Makhtesh, an erosional landform found in the Negev desert of Israel and Sinai of Egypt*Cirque , an album by Biosphere* Cirque Corporation, a company that makes touchpads...
, the bergschrund is positioned at the rear, parallel to the back wall of the corrie. It is caused by the rotational movement of the glacier. In a longitudinal glacier, the bergschrund is at the top end of the glacier at a right angle to the flow of the glacier. It is caused by the downwards flow of the glacier.
Bergschrunds extend to the bedrock
Bedrock
In stratigraphy, bedrock is the native consolidated rock underlying the surface of a terrestrial planet, usually the Earth. Above the bedrock is usually an area of broken and weathered unconsolidated rock in the basal subsoil...
and can have a depth of well over 100 metres.
In winter, bergschrunds are often filled by snow from avalanche
Avalanche
An avalanche is a sudden rapid flow of snow down a slope, occurring when either natural triggers or human activity causes a critical escalating transition from the slow equilibrium evolution of the snow pack. Typically occurring in mountainous terrain, an avalanche can mix air and water with the...
s from the mountain above it. In later summer, due to melting, it lies open and can present a very difficult obstacle to alpinists.
The bergschrund is distinct from the randkluft
Randkluft
A randkluft is the headwall gap between a glacier or snowfield and the adjacent rock face at the back of the cirque or, more loosely, between the rock face and the side of the glacier. It is formed by the melting of ice against warmer rock and may be very deep. During summer therefore, a randkluft...
(also called rimaye) which is the crevasse of which one face is the rock, back wall of the corrie. The randkluft arises in part from the melting of the ice arising from the presence of the warmer rock face. (Benn & Evans). However, the randkluft is sometimes called a bergschrund (OED
Oxford English Dictionary
The Oxford English Dictionary , published by the Oxford University Press, is the self-styled premier dictionary of the English language. Two fully bound print editions of the OED have been published under its current name, in 1928 and 1989. The first edition was published in twelve volumes , and...
).
