Fallen ice block

On May 15th, 1982, one of the wardens on Jungfaujoch noticed the descent of an unusual ice block from the hanging glacier on the south flank of Mönch. One day later the following photos were taken.

Fallen ice block
Looking from Jungfraujoch (Sphinx) towards Oberes Mönchsjoch. Ice block and track are clearly visible, as is the route towards Mönchsjochhütte SAC.
Fallen ice block
The block travelled a total horizontal distance of 470 metres; the avarage slope of the track is less than 19 degrees. In the photo: Pamela Alean.
Fallen ice block
The ice block had a volume of 55 cubic metres (+/- 25%). Since the firn surface was relatively hard when the block descended, the track is only a few tens of centimetres deep.
Fallen ice block
The shape of the track suggests that the block slid along without rotating.
Photos May 16th, 1982, Jürg Alean. Further details in Download.