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Summary Geophysical methods have recently been increasingly used in geoecological studies, including engineering and geological surveys and state monitoring of the shelf subsoil. The most widely used are various types of seismoacoustic profiling, side-scan sonar, multi-beam echo sounding. Seismoacoustic methods give an idea of the morphology of geological bodies and indirectly indicate their genesis and composition of the enclosing sediments. They are most widely used in the assessment of gaseous sediments and in the identification of gravitational processes. Side-scan sonar makes it possible to identify zones of ice scouring, to give the dimensions of relief mesoforms, as well as to estimate the intensity, type and direction of lithodynamic flows. Multi-beam echo sounding allows one to assess the morphlology of the seabed over large areas and to distinguish various genetic types of relief with their quantitative characteristics. The report provides numerous examples of the use of geophysical methods for solving various geoecological problems. It is concluded that for tasks such as determining the thickness and distribution of frozen rocks, geophysical methods at the present stage cannot give an unambiguous answer. The need to prepare a methodological manual on the use of geophysical methods for solving geoecological problems is indicated.

Summary Shallow permafrost is associated with significant potential risks for offshore construction and drilling as well as ecological risks that may occur when the permafrost is disturbed due to the human activities. Identification and mapping of the shallow permafrost areas is one of the major tasks of the site survey investigations in the Russian Arctic. Due to the lack of engineering drilling data on the Arctic shelf, remote geological and geophysical studies, such as multichannel high, very-high and ultra-high resolution (HR, VHR and UHR) seismic surveys, are increasingly being used to map and characterize the subaquatic permafrost. In the paper, we present an approach to 3D VHR reflection seismic data interpretation that allowed us to the built a volumetric model of the shallow permafrost and assess its acoustic properties in the shelf of the Kara sea. To our knowledge, this is the first ever demonstrated detailed 3D model of the shallow permafrost in the Russian Artic.