High-resolution electrical resistivity tomography applied to patterned ground, Wedel Jarlsberg Land, south-west Spitsbergen

Abstract

This article presents results of two-dimensional electrical resistivity tomography (ERT) applied to three types of patterned ground in Wedel-Jarlsberg Land (Svalbard), carried out in late July 2012. The structures investigated include sorted circles, non-sorted polygons and a net with sorted coarser material. ERT was used to recognize the internal ground structure, the shape of permafrost table below the active layer and the geometric relationships between permafrost, ground layering and surface patterns. Results of inversion modelling indicate that the permafrost table occurs at a depth of 0.5–1 m in a mountain valley and 1–2.5 m on raised marine terraces. The permafrost table was nearly planar beneath non-sorted deposits and wavy beneath sorted materials. The mutual relationships between the permafrost table and the shape of a stone circle are different from those typically presented in literature. Ground structure beneath the net with sorted coarser materials is complex as implied in convective models. In non-sorted polygons, the imaging failed to reveal vertical structures between them.Keywords: Patterned ground; permafrost; active layer; electrical imaging; Svalbard.(Published: 18 June 2015)Citation: Polar Research 2015, 34, 25678,http://dx.doi.org/10.3402/polar.v34.25678