The change in the ice conditions in the Arctic made it possible to study vast areas of the shelf by geophysical methods, including electromagnetic ones. The structure of the Arctic shelf subsea permafrost differs from the well-studied continental permafrost due to its accelerating degradation caused by the action of near-bottom waters. The features of the subsea permafrost are reflected in the electrical conductivity of rocks, since this property is sensitive to parameters such as the pore fluid salinity and pore ice/gas hydrate content. The capabilities and resolution of various marine electromagnetic technologies are analyzed, especially in application to the Arctic shelf exploration, an area with the sea depths of up to 100 m, where relict permafrost may exist.
Arctic Ocean coastal shelves, permafrost, electrical conductivity, marine geophysics, electromagnetic methods
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