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

Abstract

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