Assessment of Initial Seismicity for Offshore Platforms: a Case Study of the Pechora Sea

Abstract

Seismotectonic and seismoacoustic studies carried out during an expedition onboard the R/V Akademik Boris Petrov in the Pechora Sea revealed a paleoseismic dislocation confined to a fault zone tracing the North Ural seismic lineament. The amplitude of this dislocation (the relative displacement of its sides) makes it possible to estimate the magnitude of the paleoearthquake that occurred within the North Ural lineament. This magnitude was used to estimate the maximum seismic impacts on offshore oil and gas facilities already in operation and those being designed for construction in the northeastern Pechora Sea. These estimates differ significantly from estimates made previously. The method of searching for paleoseismic dislocations using seismoacoustic methods, as well as lineament analysis, can be used for initial assessment seismic impacts in water areas, including the Laptev Sea, as the most seismically active region of the Arctic.