TY JOUR TI Electrical conductivity features of the Arctic shelf permafrost and electromagnetic technologies for their studies KW Arctic Ocean coastal shelves KW permafrost KW electrical conductivity KW marine geophysics KW electromagnetic methods JO Russian Journal of Earth Sciences AU Piskunova, E.A. AU Palshin, N.A. AU Yakovlev, D.V. PY 2018 IS 18 PB Geophysical Center of the Russian Academy of Sciences