About Strong Earthquakes in the Early Middle Ages in the Derbent Sector of the West Caspian Coast And Seismic Potential of the Studied Section

The article discusses the initial, including completely new, materials on strong earthquakes of the early Middle Ages in the Derbent sector of the West Caspian Sea coast. Historical and written material, stone wall engravings, and archaeological, seismogeological, and late graphic (iconography) information are presented and discussed. Geodynamic features are taken into account; GPS measurement results are also used. The problem of a strong earthquake in 741–743 AD is presented in a new light. The article reviews very inaccurate and contradictory parametric characteristics of strong earthquakes from the 6th century to the present published in Russian and English scientific papers and seismic catalogs. The structural-geodynamic situation in the coastal sector under consideration is specified and the characteristics of seismogenic faults and their kinematics are refined. The eastern border of the Dagestan Mountains in the studied section is considered as a high-order regional tectonic suture. The sources of single strong events in the early Middle Ages correlate with specific active faults and are considered in accordance with their kinematics. The article compares the results obtained from general seismic zoning maps of the Russian Federation reflected on different time interval maps, including the latest generation GSZ-2015 and GSZ-2016 maps (GSZ—general seismic zoning). As a result, the hazard rate for the studied section is reduced in comparison to what is now officially accepted.