In continuous permafrost regions, pathways for transport of
sub-permafrost groundwater to the surface sometimes perforate the frozen
ground and result in the formation of a pingo. Explanations offered for
the locations of such pathways have so far included hydraulically
conductive geological units and faults. On Svalbard, several pingos
locate at valley flanks where these controls are apparently lacking.
Intrigued by this observation, we elucidated the geological setting
around such a pingo with electrical resistivity tomography. The inverted
resistivity models showed a considerable contrast between the uphill and
valley-sides of the pingo. We conclude that this contrast reflects a
geological boundary between low-permeable marine sediments and
consolidated strata. Groundwater presumably flows towards the pingo
spring through glacially induced fractures in the strata immediately
below the marine sediments. Our finding suggests that flanks of uplifted
Arctic valleys deserve attention as possible discharge locations for
deep groundwater and greenhouse gasses to the surface.