Permafrost Mapping in Two Wetland Systems North of the Tanana River in Interior Alaska 2014

Surface-based 2D electrical resistivity tomography (ERT) surveys were used to investigate the distribution of permafrost at wetland sites on the alluvial plain north of the Tanana River, 20 km southwest of Fairbanks, Alaska, in June and September 2014. The sites contained habitat types characteristic of interior Alaska, including thermokarst bog, forested permafrost plateau, and a rich fen. These habitats range from treed to open and vary in groundcover vegetation and peat thickness. Individual surveys used a cable with 56 electrodes at 2-m spacing. At a fen site, ERT surveys were performed across a mixed spruce forest area across a vegetation gradient into an open fen area. At a bog site,surveys were performed across a thermokarst bog area bordered by spruce forest and forested permafrost plateau. Some surveys partly overlap in coverage within a season, and some surveys were repeated between seasons. Different electrode array types, including dipole-dipole, extended dipole-dipole, and Wenner-Schlumberger, were compared at some sites. Data are presented in four Child Items.