Published August 2025, Pg. 4-10

Section: Geology and geophysics

UOT: 550.83

DOI: 10.37474/0365-8554/2025-08-4-10

Seismomagnetic effect reflections in the geomagnetic field prior to strong (ml 5.3–5.0) earthquakes in Lankaran and Lerik in 2024

G.J. Yetirmishli Dr. in Geol.-Min. Sc - Seismic Survey Cente

S.E. Kazimova PhD in Geol.-Min. Sc. - Seismic Survey Cente

N.B. Khanbabayev - Seismic Survey Cente

This study examines the focal mechanisms of major earthquakes that occurred in 2024 in the Lankaran and Lerik regions, along with anomalous changes in the geomagnetic field intensity near the earthquake foci. The earthquakes on May 11 and June 28, 2024, were influenced by extensional stresses. The results indicate that the formation of the seismomagnetic effect is determined by the geodynamic regime within the focal area. The spatiotemporal distribution of the geomagnetic field intensity gradient reflects the geodynamic regime in Azerbaijan.
During the Lankaran (Ml=5.3, h=20 km) and Lerik (Ml=5.0, h=18 km) earthquakes on May 11, 2024, and June 28, 2024, a seismomagnetic effect was observed on magnetometer indicators at the Ismayilli and Sheki stations 5–6 days before the earthquakes, characterized by a decrease in geomagnetic anomalies corresponding to extensional and normal-slip stresses. On the geomagnetic anomaly maps, the Jalilabad (+250 nT) and Imishli-Kurdamir (+350 nT) magnetic intensity maxima are clearly reflected, with stress directed northwest, while the center of the study region shows closed contour lines. Analysis revealed that, following these earthquakes, stress in these areas has not yet been fully released.

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