The results of the reconstruction of source provinces are presented for the Lower Cretaceous deposits of the northwestern Caucasus. The resulting data have made it possible to clarify the paleoenvironments of the sedimentation and identify the source areas of clastic material. The main source of the clastic material was located northeast of the studied territory near the Scythian Plate; there was also a source in the southeast, in the Greater Caucasus region. In the Berriasian–Valanginian, Upper Jurassic reefs were periodically eroded along the southern edge of the Scythian Plate.

The Russian sector of the Eastern Arctic is characterized by large basins with thick sedimentary filling, primarily on the shelf and continental slope of the seas of the Arctic Ocean. A number of geological, geophysical, and geochemical features point to a hydrocarbon potential. At the same time, the age and composition of the sedimentary infill of the shelf basins have been controversial until now due to the lack of wells drilled in the shelf area. Six stratigraphic wells were drilled with core sampling in the eastern Laptev Sea (Anisin-Novosibirsk block owned by Rosneft) with a depth of 100 to 199.5 m during the Rosneft Stratigraphic Drilling in Arctic (RoSDAr) project in 2021. The results of complex biostratigraphic studies of the core show that the oldest strata in the well sections are Upper Barremian - Lower Aptian deformed silty mudstones (folded basement assemblage) overlain with angular unconformity by sands, silts, and clays of the Paleocene. The wells also penetrate the Eocene, Oligocene, and Miocene-Quaternary clastic rocks. A comprehensive analysis of stratigraphic drilling and seismic data refines the geological models of the region and provides better understanding of its hydrocarbon potential. The data show that Cenozoic strata play a more significant role in the sedimentary cover of the Laptev Sea than was previously assumed.

An integrated approach to the study of the Maastrichtian deposits of the Darya River (North Caucasus) section served as a basis for reconstructing the sedimentation conditions. As a result of our research, we have made conclusions about the biotic and abiotic events of that time. The stratigraphic position of the section has been clarified and its zonal subdivision by foraminifers has been defined. The paleogeographic and paleoclimatic environments have been reconstructed. It has been revealed that there was a warm-water basin (from shallow-sea to moderately deep-water one) with a normal salinity and an irregular sedimentation rate in the region in the Maastrichtian.

The results of a comprehensive study of the deposits of the Fanar horizon of the Lower Cretaceous of the Northwest Caucasus are presented, which have made it possible to establish the conditions of their formation and the source areas of clastic material. It has been revealed that the studied territory was a frontal area of the delta, in which sandy and sandy-clay deposits accumulated in separate distributing channels. The sandstones of the horizon have good reservoir properties with a porosity coefficient (Kp) of up to 21.3

The data on the first findings of benthic fauna (foraminifera and mollusks) in the Pliocene-Quaternary sediments of the northeastern part of the Laptev Sea of the Arctic basin, obtained by studying the core of the SSDAN-1 well, are presented. The position of the Quaternary-Pliocene boundary in the borehole section is clarified, and paleoenvironments in the Arctic paleobasin are defined.

The continuous Turonian-Coniacian succession, exposed in the Shapsug quarry (northwestern Caucasus) composed of rhythmic carbonate strata of the hemipelagic and pelagic type, have been studied comprehensively. Foraminiferal zones, corresponding to the zonation recognized in the Coniacian Global Boundary Stratotype Section and Point (GSSP), have been identified. Chemostratigraphic (isotope) studies determine the levels of abiotic events traced in this section and in the GSSP for the base of the Coniacian Stage. The Shapsug section may be proposed a possible auxiliary section of the base of the Coniacian for the Russian Federation.

The results of a comprehensive study of the reference section of the Upper Maastrichtian of Mount Klementyev (South-Eastern Crimea), composed of a terrigeneous-carbonate strata. It was found that sedimentation occurred in relatively deep-water conditions. Biostratigraphic analysis of benthic and planktonic foraminifera assemblages made it possible to identify foraminiferal zones in the section and confirm the deep-water type of sedimentation in the basin at this interval.

Lithological and X-ray phase analysis of Lower Cretaceous clay deposits in the northwestern Caucasus has allowed us to establish the conditions of their formation and sources of erosion of clastic material. It has been found that the studied sediments were formed in normal marine, relatively deep-water conditions of the shelf. The clays of the Lower Cretaceous are characterized as rocks with high conservation properties, which has determined not only the conservation of oil deposits but also the conservation of gaseous hydrocarbons.

The results of a comprehensive study of an Upper Maastrichtian reference Mt. Klementyev section (Southeastern Crimea), consisting of a terrigenous–carbonate sequence, are presented. It is established that sedimentation occurred in relatively deep-sea conditions. Biostratigraphic analysis of assemblages of benthic and planktonic foraminifers made it possible to recognize the foraminiferal zones in the section and to confirm deep-sea sedimentation during this period.

The Stratigraphic Drilling Project of the Russian Arctic Shelf conducted by the PJSC Rosneft is aimed at discover the stratigraphic age and rock composition of sedimentary succession of its subsurface. In 2021, six shallow wells for the first time have been drilled with core sampling in the east of the Laptev Sea. Drilling revealed folded sedimentary succession dated back to the Late Barremian – Early Aptian. The synrift complex overlying unconformably dates to the Paleocene. The upper strata dates from Eocene to Pleistocene and contains significant hiatuses. The data discovered together with the results of seismic interpretation clarified the regional geological model and dated the stages of its tectonic evolution.

The Stratigraphic Drilling Project of the Russian Arctic Shelf, conducted by the Rosneft Oil Company, focuses their attention on the stratigraphic age and composition of rock complexes of the sedimentary basins. In 2021, six shallow boreholes for the first time were drilled with core sampling in the eastern part of the Laptev Sea. Drilling recovered sedimentary rocks of the folded basement that have been dated to the Late Barremian–Early Aptian. The synrift complex lying with angular unconformity has been dated to the Paleocene. The section of the overlying Eocene–Pleistocene sediments contains significant hiatuses. The data obtained by drilling together with the results of seismic interpretation allowed us to clarify the regional geological model and to date the stages of its tectonic evolution.

—The lithological and geochemical characteristics of the Meso-Cenozoic interval of the Leskinskaya borehole section (the mouth of the Yenisei River) and its paleogeographic and paleoclimatic characteristics are given.

The results of a study of calcareous nannofossils found for the first time in the lower part of the Stolbovaya Group of the Kamchatsky Mys Peninsula in Eastern Kamchatka are presented. Two assemblages of different age are identified, with one assigned to the Upper Cretaceous and the other to the Paleogene (not older than the Lutetian Stage of the Middle Eocene). These data make it possible to refine the age of terrigenous–tuffaceous sequences in the lower part of the Stolbovaya Group, which are poor in organic remains.

This paper presents the results of a comprehensive study of the Maastrichtian sequence of Mount Kyz-Kermen located in the Southwestern Crimea. The section consists of a rhythmically bedded carbonate sequence gradually replaced by carbonate sandstones. The study of rocks in thin sections made it possible to identify eight lithotypes, and the chemical analyses yielded variations in individual elements in the rock composition. The interpreted data on planktonic and benthic foraminifera made it possible to determine the age of deposits within the accuracy of zones and beds with fauna and to find one more supposed break in the middle of this section, coinciding with a noticeable change in the rock composition. The assay analysis of foraminifera assemblages together with lithological and geochemical results made it possible to determine that the studied section was formed in open carbonate-platform conditions at the depth of the middle–outer shelf.

The results of a comprehensive study of the boundaries of the Turonian–Coniacian in the Upper Cretaceous deposits of the Abinskii region of the Northwestern Caucasus, composed of rhythmically constructed carbonate strata of the hemipelagic type, are presented. Biostratigraphic analysis of foraminifera complexes made it possible to identify zones in the section that are comparable to those proposed for the Point of the Global Stratotype of the boundary of the Coniacian in Germany. On the basis of chemostratigraphic (isotope) studies, the levels of abiotic events traced in the section and other territories have been established. The Shapsug section, after further study, can be proposed as a possible Hypostratotype (Limitotype) of the Turonian–Coniacian boundary for the territory of the Russian Federation.

Paleotemperature curves for water masses and average annual temperatures were constructed from our own and published data for Central and Eastern Tethys for the Jurassic-Quaternaryfor the first time.

The results of integrated study of the Turonian–Coniacian sediments from the Abinsky district (Northwest Caucasus), which are represented by a rhythmic terrigenous-carbonate sequence, are discussed. The use of microfacial, X-ray diffraction, isotope, and micropaleontological analyses allowed us to reveal important changes in abiotic and biotic evolution during this interval. The peculiarities of carbonate sedimentation, as well as changes in the composition of foraminiferal assemblages, helped to establish fluctuations in the relative sea level, whereas isotopic studies assisted in defining climatic fluctuations. During the periods of accumulation of carbonate and clayey material, the area was occupied by a relatively deep-water open-sea basin with normal salinity. In the background of high temperatures, cooling pulses are also recorded within the studied interval. The position of the Turonian–Coniacian boundary in the section is revised.

Representatives of the foraminiferal family Elphidiidae Galloway, 1933 are widely distributed in the Cenozoic deposits of the Far East, where the main oil-and-gas fields of the region are concentrated. Species of this family are important stratigraphic and correlative markers and are used as index species for local and regional stratigraphic zones and for beds with fauna. Some characteristic species are described taxonomically.

The paleotemperature curves for water masses and average annual temperatures have been plotted for the first time on the basis of original and published data for the Central and Eastern Tethys for the Jurassic–Quaternary period.

В учебном пособии рассматриваются наиболее важные аспекты полевых методов геологических исследований на примере Бахчисарайского района Крыма. Для студентов геологического факультета МГУ им. М.В. Ломоносова, а также всех специалистов и студентов-геологов, использующих в работе полевые методы геологических исследований