Movement Studies on a Hanging Glacier in Relation with an Ice Avalanche

• Published in: Journal of Glaciology
• Main Author: Flotron, André
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1977
• Subjects: Earth-Surface Processes; The Weisshorn; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/s0022143000029592; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000029592

Abstract In 1972 the state of a hanging glacier on the Weisshorn gave cause for alarm, as part of it seemed to be accelerating and a repetition of an earlier avalanche of ice seemed possible (see Röthlisberger, previous abstract). For this reason movement surveys were undertaken. The various surveying methods applied on the Weisshorn are outlined and the accuracy of the measurements is given. By least-square analysis different types of curves have been fitted to the data for velocity versus time. The best fit obtained so-far has been with hyperbolae. The confidence of extrapolations from such curves is discussed in relation to forecasts. By evaluating repeated photographs taken by an automatic camera from a single position, using a stereo plotter, the flow pattern has been established at the surface, part of the front, and one of the lateral faces of the ice mass. Changes with time caused by the deformation of the ice mass, the formation of crevasses and the crumbling away of the ice at the edge have been observed.