Influence of Mid-Oceanic Ridges on Seismicity of Novaya Zemlya Archipelago

Abstract

The influence of the mid-oceanic ridges (MOR), including the Gakkel Ridge and the geological system Knipovich Ridge–Trough Lena, on the seismicity of the Novaya Zemlya archipelago area for 1980‒2022 is considered. For each geological element under consideration, we compiled seismic catalogs with a single unified magnitude mbISC for an equivalent comparison of information, and the annual seismic energy was calculated, and graphs of its distribution by year were constructed. We performed analytical modeling based on the Elsasser model describing the process of local stress transfer in a rigid elastic lithosphere underlain by a viscous asthenosphere, and made quantitative calculations of the disturbance propagations from MOR. The time intervals through which disturbances from MOR reach the Novaya Zemlya archipelago are 1‒2 years for the geological system Knipovich Ridge–Trough Lena and 3‒5 years for the Gakkel Ridge. The maximum joint contribution to the level of seismic activity of various geological and tectonic structures of the MOR can reach 40‒60% of the applied disturbances values, which is a sufficient condition for the influence on seismicity of the Novaya Zemlya orogen. The most geodynamical active structures and zones of concentration of tectonic stresses are identified.