ABSTRACT
Mud polygons forming in a valley train deposit in Teleki Valley on Mount Kenya were studied with respect to their physical, mineralogical, chemical, and biological characteristics. Developing in fine-grained alluvium of postglacial age, these polygonal systems are composed of numerous, and nearly isomorphous units, that appear close to existing drainages in areas stripped of vegetation cover. Stream erosion and animal activity (particularly rodents and Mount Kenya hyrax) appear to be primarily responsible for the loss of plant cover. Freeze-thaw activity was not observed to assist in developing polygonal ground shape, but field tests show that periodic wetting and drying results in closure and reopening of polygonal cracks. The absence of expandable clay minerals is not considered to limit the growth and development of mud polygons.
