ABOUT STRONG EARTHQUAKES IN THE EARLY MIDDLE AGES ON THE DERBENT SECTION OF THE WEST-CASPIAN COAST AND SEISMIC POTENTIAL OF THE STUDIED SECTION

A.A. Nikonov

Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia

e-mail: nikonov@ifz.ru

Abstract. The article discusses the initial, including completely new, materials on strong earthquakes of the early Middle Ages on the Derbent section of the West coast of the Caspian Sea. Historical, written and graved on stone walls, archaeological, seismogeological, as well as late graphic (iconography) information is brought and discussed. Geodynamic features are taken into account, the results of measurements in the GPS network are used, too. The question of a powerful earthquake of 741–743 is presented in a new light. A review is given of published in scientific papers, in Russian and English, in seismic catalogs, of very inaccurate and contradictory parametric characteristics of strong earthquakes from the VI century to the present. The structural-geodynamic situation in the coastal sector under consideration is specified and the characteristics of seismic generating faults and their kinematics are specified. The eastern border of Mountain Dagestan on the studied section is considered as a high-order regional tectonic seam. The foci of single strong events of the early Middle Ages correlate with specific active faults and are considered in accordance with their kinematics. A comparison is made of the results obtained with the maps of general seismic zoning of the Russian Federation reflected on different time interval maps, including the maps of the latest generation GSZ-2015 and GSZ-2016 (General seismic zoning). As a result, the rate of danger for studied section is reduced in comparison with what is now officially accepted.

Keywords: Eastern Caucasus, western coast of the Caspian Sea, Mountain Dagestan, Caspian (Derbent) gates, Derbent, seismogeology, seismicity, geodynamics, active faults, modern movements, historical earthquakes, seismic catalogs, seismic potential, maps of the seismic zoning.

About the author

NIKONOV Andrei Alekseevich – Doctor of a Geological and Mineralogical Sciences, Professor, Chief Researcher, Schmidt Institute of Physics of the Earth, Russian Academy of Sciences. Russia, 123242, Moscow, Bolshaya Gruzinskaya st., 10, building 1. Tel.: +7 (499) 252-78-85. E-mail: nikonov@ifz.ru

Cite this article as: Nikonov A.A. About strong earthquakes in the early Middle Ages on the Derbent section of the West-Caspian coast and seismic potential of the studied section, Voprosy Inzhenernoi Seismologii (Problems of Engineering Seismology). 2019. V. 46, No. 4. P. 5–28 [in Russian]. https://doi.org/10.21455/VIS2019.4-1

English translation of the article will be published in Seismic Instruments, ISSN: 0747-9239 (Print) 1934-7871 (Online), https://link.springer.com/journal/11990