Abstract
This article provides a comparative analysis of the anomalies in the values of the regional gravity field with the spatial distribution of the earthquake epicenters in the Javakheti Highland. It is shown that the epicenters of earthquakes with magnitudes M ≥ 4 are confined to the gradient zones, where significant relative minima and maxima of the anomalies of the gravitational field in the Bouguer reduction are observed. The average mechanisms of earthquakes in individual seismogenic blocks of the region were obtained for the observation period from 1971 to 2015, which indicate that normal faulting is the dominant type of movements in the earthquake foci. The result is explained by the processes occurring in the subcrustal layer and leading to the decompaction of matter in the uplift zones, which is one of the main factors in the occurrence of negative gravity anomalies in the area under consideration.
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The work was carried out as part of State Task project no. 0144-2019-0011 of the of Institute of Physics of the Earth.
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Kazaryan, K.S., Burmin, V.Y. & Avetisyan, A.M. Comparison of Seismicity and Average Focal Mechanisms of Javakheti Highland Earthquakes with Regional Gravitational-Field Anomalies. Izv. Atmos. Ocean. Phys. 56, 1423–1431 (2020). https://doi.org/10.1134/S0001433820110031
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DOI: https://doi.org/10.1134/S0001433820110031