Boulder Polygons and Stripes in the Cairngorm Mountains, Scotland
Abstract Measurements of widths, diameters and boulder sizes of patterned ground in the Cairngorm Mountains indicate two sorts of stripes and polygons (fine and coarse). Pipkrake and boulder-inclination observations and measurements suggest that fine polygons are produced by heave and their sizes ar...
| Published in: | Journal of Glaciology |
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| Main Author: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Cambridge University Press (CUP)
1971
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1017/s0022143000022073 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000022073 |
| Summary: | Abstract Measurements of widths, diameters and boulder sizes of patterned ground in the Cairngorm Mountains indicate two sorts of stripes and polygons (fine and coarse). Pipkrake and boulder-inclination observations and measurements suggest that fine polygons are produced by heave and their sizes are dependent upon the frequency of boulders large enough to be resistant to heave, which in turn depends upon climatic severity. The lack of orientation, angle of boulder inclination, hemispherical shape, high relative size dispersion and lithological dependence of coarse polygons indicate a selective weathering origin. The frequency of low inclination of boulders in stripes suggests an origin due to solifluction, whereby large immobile or relatively slower-moving boulders impede soil (and smaller boulder) movements and control stripe spacing. Movement observation and lichenometry indicate that fine polygons and stripes and bare coarse polygons are active at the present time and that coarse stripes and vegetated coarse polygons probably date from the Little Ice Age. |
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