331 ISSN 0016-8521, Geotectonics, 2020, Vol. 54, No. 3, pp. 331–355. © Pleiades Publishing, Inc., 2020. Russian Text © The Author(s), 2020, published in Geotektonika, 2020, No. 3, pp. 55–81. Mesozoic–Cenozoic Structure of the Black Sea–Caucasus–Caspian Region and Its Relationships with the Upper Mantle Structure V. G. Trifonov a, *, S. Yu. Sokolov a , S. A. Sokolov a , and K. Hessami b a Geological Institute of the Russian Academy of Sciences, Moscow, 119017 Russia b International Institute of Earthquake Engineering and Seismology, North Dibajee, Farmanieh, Tehran, 19537–14453, Iran *e-mail: trifonov@ginras.ru Received January 14, 2020; revised January 30, 2020; accepted February 4, 2020 Abstract—Mesozoic‒Cenozoic tectonic zoning and its evolution are characterized by analysis of geological data on the Black Sea–Caucasus–Caspian region. The following tectonic zones were located in succession to the north of the Mesotethys Ocean in the Early Jurassic: the mobile zone on the Hercynian basement; the Moesian–Black Sea–Trans-Caucasus minor plate with the Precambrian–Baikalian basement, which expe- rienced the Hercynian tectonic and magmatic reworking in the Lesser Caucasus; the relatively deep-water Crimean–Caucasus–South Caspian Trough on the continental crust that thinned in the process of its exten- sion; and the southern margin of the Scythian Plate with a thin sedimentary cover. In the Caucasus, the southern and northern slopes of the deep-water axial trough have been identified, where thick shelf deposits accumulated. Subduction began in the northern margin of the Mesotethys in the Bajocian and island-arc vol- canism occurred in the Somkheti–Karabakh zone and Eastern Pontides, the Trans-Caucasus part of the Moesian–Black Sea–Trans-Caucasus Plate, and the southern slope of the Crimean–Caucasus–South Cas- pian Trough. The volcanism in the Somkheti‒Karabakh zone and the Eastern Pontides lasted into the Cre- taceous. The area of island-arc volcanism was inherited by the Eocene collisional volcanic belt. The Crimean part of the Crimean–Caucasus–South Caspian Trough and its northern slope in the Caucasus underwent Cimmerian deformation and shelf facies accumulated there after deformation up to the Miocene, while rel- atively deep-water sedimentation occurred in the Caucasus–South Caspian part of the Crimean–Caucasus– South Caspian Trough. The Western and Eastern Black Sea basins of extension originated in the Cretaceous on the continental crust of the Moesian–Black Sea–Trans-Caucasus Plate, which thinned in the basins as they were filled by Late Cretaceous, Paleogene, and Miocene marine deposits. In the Pliocene–Quaternary, total undifferentiated subsidence and sedimentation occurred in the Black Sea, and subsidence of the South Caspian, Azov‒Kuban, and Terek‒Derbent basins accelerated. Several phases of Middle and Late Miocene fault–fold deformation formed local uplifts in the mountainous parts of the region. The total uplift of moun- tain systems occurred in the Pliocene–Quaternary. The formed crustal structures and the velocity inhomo- geneities in the upper mantle were compared, which showed that many inhomogeneities were obliterated by sublithosphere flows that spread out of the Ethiopian–Afar superplume. In mantle volumes, where the flow intensity weakened, relics of subducted slabs remained. They are slabs of the Neotethys in the Zagros and the Mesothethys in the Lower Kura Basin, and slabs of the Scythian Plate lithosphere underthrust under the Central Caucasus and more weakly under Steppe Crimea during the Hercynian subduction. Keywords: Crimea, Caucasus, Black Sea, Caspian region, Mesozoic, Cenozoic, tectonic zoning, tectonic evolution, upper mantle, seismic tomography data DOI: 10.1134/S0016852120030103 INTRODUCTION The paper analyzes geological and geophysical data on the structure and Mesozoic–Cenozoic tectonic development of the Black Sea–Caucasus–Caspian region [4, 9, 13, 28, 29, 32, 48, 52, 90]. The objective is to reveal the tectonic zoning common to the entire region and its transformations during the Mesozoic and Cenozoic and to compare the structure of the crust that changed during this evolution with struc- tural inhomogeneities of the sublithospheric upper mantle, determined on the basis of seismotomography data [76]. The study region is a part of the Alpine–Hima- layan folded belt and encompasses the eastern Black Sea, the Mountain Crimea, the Eastern Pontides, Greater and Lesser Caucasus, Alborz, and the South and, partially, the Middle Caspian (Fig. 1). In the north, the region borders on slightly deformed parts of the Paleozoic Scythian and Turan plates. The south- ern boundary is the Mesotethys suture (northern branch of Neotethys, according to [48, 86]).