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Two year study on a rapidly evolving Thermokarst in a discontinuous permafrost watershed: Results and implications Prathap Kodial and Horacio Toniolo The role of sediment transport in the development
of cryogenic features such as thermokarsts has received little attention
in the recent past. The current study is an attempt to better understand
the processes underlying the rapid growth of a thermokarst located in
the Caribou-Poker Creeks Research Watershed (CPCRW), which has discontinuous
permafrost distribution. Within a short span of two summers, one dry-warm
and the other wet-warm, the study area has progressed from a hummocky
terrain to a well defined channel topography. Suspended sediment concentration
and discharge analyses indicate high sediment flows following a precipitation
event. Mass sediment flows, resulting from interflow within the active
layer, was indicated by piping. Block failure was a consequence of fluvio-thermal
erosion evidenced by "thermo-erosional niche" features. Topographical
surveys spanning the two field seasons; quantify the upstream erosion
of more than 10 meters. Accelerated growth of the thermokarst has made
the adjacent areas highly susceptible to secondary geomorphologic features.
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