Spatiotemporal Relationship between Arctic Mid-Ocean Ridge System and Intraplate Seismicity of the European Arctic

Abstract

AbstractIn this article, we investigate the influence of the Arctic mid-ocean ridge system (AMORS), including the Gakkel and Mohns ridges, and the Knipovich ridge–Lena trough (KL) segment, on seismicity of the Novaya Zemlya archipelago area (NZ) and the northernmost margin of the East-European Platform (EEP) for 1980–2019. For each individual area, the annual seismic energy was obtained by adding the energies of all earthquakes. To do this, we have converted various types of magnitude by different seismic networks into moment magnitude Mw. We compiled the updated catalog for the NZ, the northern EEP, and the northern part of the Ural fold belt (UFB). As a result, we constructed time distributions of annual seismic energy releases for each composing ridges of AMORS, NZ, and EEP combined with UFB. A model based on the Elsasser’s one describing the transfer of lithospheric stress disturbances in the horizontal direction was built, and quantitative calculations of the disturbance propagations from AMORS were performed. Results are in good agreement with the annual seismic energy time lags between rifts and NZ and EEP together with the UFB. We calculated correlation coefficients between the seismic energy releases over the time for the structures, enabling identification of the characteristic excitation cycles and estimation of the interval of disturbance transfer from AMORS. As a result, disturbances from the Gakkel ridge appear 3 yr later in NZ, from the KL segment in 4 yr, and from the Mona ridge in 8 yr. For the EEP + UBF combined area, we found the following disturbances spreading lags as 7 yr for the Mona ridge, 4 yr for the KL segment, and 5 yr for the Gakkel ridge. The obtained damping amplitudes of the disturbance spreading from the arctic ridges are sufficient to affect the intraplate seismic activity.