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Composite paleotemperature curves (values of average annual temperature and sea surface temperature) for high and low latitudes of Northern Eurasia have been compiled. Based on them, a model of the climatic history of the Northern Hemisphere in the Mesozoic-Cenozoic was compiled. The relationship of climate variations with other significant geological events — cycles of eccentricity of the Earth’s orbit, impact events, inversions of the geomagnetic field is analyzed.

In this article, the possibilities of statistical analysis methods were demonstrated on the example of studying modern bottom sediments in the western part of the Barents Sea. As a result of cluster and dispersion analyses, regularities in the distribution of granulometric types of modern bottom sediments and organic carbon dissolved in them with depth within the sublittoral and bathyal zones of the sea were established. Based on the results obtained, it was concluded that the size distribution of sediments was due to the mechanical differentiation of sedimentary material as it was transported by sea currents, as well as the distance from the main sources of drift — Novaya Zemlya, the Kola Peninsula and Svalbard. At the same time, the accumulation of organic carbon in bottom sediments was associated with the peculiarities of the distribution of communities of marine organisms within the considered facies zones. The high content of organic carbon in the bathyal zone of the sea was associated with an increase in primary productivity here, as well as with the transfer by sea currents of the accumulated biogenic material of the littoral and sublittoral zones towards the bathyal.

In the article, methods of mathematical statistics were used to study the processes of sedimentogenesis and early diagenesis of the surface sediments of the Kara Sea. Correlation analysis established two groups of oxides associated with certain granulometric types of deposits. As a result of applying one-way analysis of variance, the regularity of the distribution of sand, silt and pelite was established in accordance with the conditions of sedimentation based on differences between their average values. Based on these data, maps of the distribution of sand, silt, and pelite were constructed within the studied part of the Kara Sea. On the basis of statistical data, some features of the main factors of sedimentogenesis for this region were revealed. As a result of the established relationship between the Mn/Al, Mn/Fe, MnO/SiO2 ratios and depth, using a one-dimensional regression analysis, the intensity of early oxidative diagenesis within the shelf zone of the Kara Sea was studied.

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 a geochemical study and paleogeographic, paleoclimatic interpretation for a cyclically constructed section of upper Cretaceous deposits near Volsk city, Saratov region, are presented. Elementary formation cyclites and cyclic variations of a number of certain parameters were associated with the Milankovich astronomical-climatic cycles. The curves of changes of paleotemperature, humidity, paleobathymetry were compiled. The results obtained give an idea of the migration of the arid belt boundaries in the upper Cretaceous and the overall climatic zonation, which is important for regional and global paleoclimatic reconstructions, as well as the history of the development of shelf seas that covered the Russian plate (especially Ulyanovsk-Saratov trough). Paleotemperatures of the land surface in the denudation areas are obtained from the chemical index of alteration (CIA). In the Turonian-Campanian interval selected climatic cyclicity, including period of relative cooling (Turonian–Coniacian) with paleotemperature about 20 °С, the period of relative warming in the mid-late Campanian (20–24 °С), the cooling time at the end of the late Campanian (19–21 °С) and the period of warming at the turn of the Campanian and Maastrichtian and in the early Maastrichtian time. In Maastrichtian age, there are two climatic cycles, beginning with a time of relative cooling (about 19 °С) and ending with a time of relative warming (about 20 С, at the end of Maastrichtian to 25 °С). The cycles of climate humidity change are also determined: two cycles in Campanian time, three cycles in early Maastrichtian, and one cycle in late Maastrichtian. The boundary of the early and late Maastrichtian corresponds to the change of arid conditions to humid ones. The paleobatimetry curves show transgressive-regressive cycles: one in the late Turonian-Coniacian time, two in the late Campanian time, five in the early Maastrichtian time, and one in the late Maastrichtian time. Depth variations were estimated: in the Turonian-Coniacian time in the range of 70–80 m, in the Campanian-Maastrichtian time, the paleobatimetry consistently increased and changed from 100 to 200 m (on average about 150 m). The results obtaired give and idea of the migration of the boundaries of the arid belt in the Late Creataceous and main features of the climatic zonation, which is important for regional and global paleoclimatic reconstructions, as well as for the history of the development the Russian plate in the Ulyanovsk-Saratov region.

The results of geochemical research of the cyclic section of the Upper Cretaceous deposits near Staryi Oskol town at Belgorod province and paleogeographical and paleoclimatic interpretation of these data were given for the first time.

We present the results of a geochemical study and their paleogeographic and paleoclimatic interpretation for a cyclically constructed section of the Upper Cretaceous deposits near Staryi Oskol in the Belgorod region.

The results of a geochemical, paleogeographic, and paleoclimatic study of a cyclically constructed section of upper Cretaceous deposits near Vol’sk city (Saratov oblast) are presented. Elementary layered cyclites and cyclic variations of several certain parameters were associated with the Milankovich astronomical-climatic cycles. Paleotemperature, humidity, and paleobathymetry curves were compiled. Paleotemperatures of the land surface in the denudation areas were obtained from the chemical index of alteration (CIA). Climatic cyclicity was established in the Turonian–Campanian interval, including a period of relative cooling (Turonian–Coniacian) with a paleotemperature of approximately 20°С, the period of relative warming in the mid–late Campanian (20–24°С), the cooling time at the end of the late Campanian (19–21°С) and the period of warming at the turn of the Campanian and Maastrichtian and in the early Maastrichtian time, there are two climatic cycles in Maastrichtian age, beginning with a time of relative cooling (approximately 19°С) and ending with a time of relative warming (approximately 20°С, at the end of Maastrichtian to 25°С). The cycles of climate humidity change are also determined: two cycles in Campanian time, three cycles in early Maastrichtian, and one cycle in late Maastrichtian. The boundary of the early and late Maastrichtian corresponds to the change of arid conditions to humid ones. The paleobatimetry curves show transgressive–regressive cycles: one in the late Turonian–Coniacian time, two in the late Campanian time, five in the early Maastrichtian time, and one in the late Maastrichtian time. Depth variations were estimated: in the Turonian–Coniacian time in the range of 70–80 m, in the Campanian–Maastrichtian time, the paleobatimetry consistently increased and changed from 100 to 200 m (on average approximately 150 m). These results provide an idea of the migration of the boundaries of the arid belt in the Late Creataceous and main features of the climatic zonation, which is important for regional and global paleoclimatic reconstructions, as well as for the history of the development the Russian Plate in the Ulyanovsk–Saratov region.

Geochemical studies of Sarmatian clay and siltstone of the Kerch Strait and Taman Peninsula were carried out for the first time in order to identify the paleogeographic features of sedimentation. Based on the results of the interpretation of the geochemical data, the curves of paleosalinity and paleobathymetry of the Yenikale Strait in the eastern part of the Paratethys Ocean were determined. Two regressive (Early Sarmatian; from the middle of the Late Sarmatian) and two transgressive (Middle and the beginning of the Late Sarmatian; the end of the Late Sarmatian–early Meotian) stages were distinguished in the evolution of the studied area. The data on salinity (in ppm) were obtained. The effectiveness of the applied methodology for interpretation of geochemical data in paleogeographic reconstructions, which subsequently can be successfully applied to deposits that lack fossil remains or are characterized by a poor indicator function of the fauna and flora species, has been confirmed.

As a result of an analysis of published works, a database on paleotemperatures in the Arctic and Subarctic regions based on marine invertebrate skeletons, marine palynomorphs, dinosaur teeth, analysis of the ability of reptiles to lay eggs at low temperatures, terrestrial floral assemblages (CLAMP-analysis), the presence of coal interbeds in continental deposits within the Arctic region, and on membrane lipids of glycerol and dialkylglycerol tetraether in marine sediments and glendonite was assembled. Based on the obtained data, a paleotemperature curve for the Cretaceous–Cenozoic stage of geological history of the Arctic region was constructed. The general trends of this curve are in consistent with the global paleotemperature curve (Scotese, 2015) (with the exception of the cooling period in the Tortonian due to local factors). In total, 16 climatic cycles in the climatic history of the Arctic, including 16 climatic minima (including the glaciation in the Northern Hemisphere) and 15 climatic maxima have been established.

A section of Upper Carboniferous and overlying Jurassic sediments in the area of a buried karst depression in the northwestern part of Moscow was studied. According to conodont zoning, it was revealed that in the section of the karst depression the Perkhur Formation directly lies on the Voskresensk Formation altered by karst processes. It was shown that the absence of the Neverovo Formation in the section is associated with landslide deformations, which occurred in the Middle Jurassic (Kudinovo) time, that is, the movement of a block of the Perkhurovsky limestones, which was located hypersometrically higher on the slope of the karst paleodepression.

Cretaceous calcareous nannoplankton was studied in the Lower Cretaceous Rezanaya and Biasala and Upper Cretaceous Belogorsk, Prokhladnoe, and Kudrino formations of the Bakhchisarai region of the southwest Crimea. The age of the host rocks was refined according to calcareous nannoplankton. No nannoplankton zone was identified in the Rezanaya Formation; the Biasala Formation probably contains part of the NC5 Zone. The Belogorsk and Kudrino formations host the (partly) UC3 Zone (Subzone b) and the UC20 Zone (Subzone UC20b), respectively. No upper and lower boundaries of zones were traced.

This article discusses the structural peculiarities and new data on the distribution of calcareous nanoplankton from Cretaceous–Paleogene boundary deposits of the central area of Piedmont (Predgornyi) Crimea. Both Maastrichtian and Danian rocks contain abundant Cretaceous nanoplankton assemblages. Danian nanoplankton is scarce, characterized by a poor degree of preservation, or even absent. Upper Maastrichtian rocks contain the species Tranolithus orionatus (=Tranolithus phacelosus Stover), which is typical of the Lower Maastrichtian and unknown in the Upper Maastrichtian of the European section; the only reported section of this age containing this species is in southwestern Tunisia. The NP2–NP4 zones are distinguished in the Danian deposits. The paleogeographic problem is also addressed.

The calcareous nannoplankton of the Upper Paleocene and Eocene deposits from the Bakhchisaray district of the Southwest Crimea has been studied. It has been compared with the coeval complexes studied earlier and the following zones have been identified: the Kacha Formation corresponds to zones NP6–NP8 (?), the Bakhchisaray Formation is NP12, and the Simferopol Formation is NP13–NP14. According to the species composition, calcareous nannoplankton inhabited the normal salty shelf sea in the tropical belt.

The calcareous nannoplankton of the Upper Paleocene and Eocene deposits from Bakhchisaray region of the South-Western Crimea was studied, it comparison with the coeval complexes studied earlier was made and zones were identified. Kacha Formation corresponds to zones NP6–NP8 (?), Bakhchsarai Formation — to NP12 zone, Simferopol Formation — to zones NP13–NP14. According to the species composition, it was found that the calcareous nannoplankton lived in the normal-salt shelf sea, in the tropical belt.

The composition and origin of the Visean–Serpukhovian deposits in the southern part of the Moscow Syneclise have been characterized based upon generalizations of our own results and analysis of published and unpublished data. The levels of karst-influenced rocks correspond to the shallowest biogenic carbonate organogenic-clastic sediments of the initial and final phases of the eustatic cycle, i.e., the early transgression (transgressive system tract) and the late regression (the second half of the high-standing tract). Alluvial sands of the Oka River have been found in the karst cavities. A generalized model of the sequence has been proposed and a sequence stratigraphic interpretation of the studied section has been carried out.

Composition and origin of Visean–Serpukhovian deposits of the Southern part of the Moscow syncline based upon generalizations of our own results and analysis of published and unpublished data were specified. The levels of karst-influenced rocks correspond to the shallowest biogenic carbonate organogeneous-clastic sediments of the initial and final phases of the eustatic cycle, i.e. the beginning of the transgression (the transgressive system of the tracts) and the end of the regression (the second half of the high-standing tract). In the karst cavities alluvial sands of the Oka river were found. A generalized model of the sequence was proposed and a sequential-stratigraphic interpretation of the studied section was carried out.

The composition and origin of the Callovian–Oxfordian deposits of the Sudak Bay were characterized on the basis of the generalization and analysis of our own results, as well as published and unpublished data. The botanical future was first implemented for the geological mapping of the Oxfordian deposits.

Composition and origin of Callovian–Oxfordian deposits of the Sudak Bay based upon generalizations of our own results and analysis of published and unpublished data were specified. A botanic feature for geological prospecting of Oxfordian limestones was used for the first time.

Geological and geophysical materials were analyzed to study the peculiarities of the geological structure of the Vikulov Formation within the Vodorazdelnyi license area. The presented data makes it possible to characterize the geological structure of the studied area more informatively and make an interpretation of the seismic data. The analysis of geological information (well logging and test results) confirms the established level of the water–oil contact in the studied area of the field, making it possible to recalculate the oil reserves.

The analysis of geological and geophysical materials in order to study the peculiarities of the geological structure of the Vikulov Formation within the Vodorazdel license area was carried out. The presented factual material makes it possible to characterize the geological structure of the investigated area more informatively and for interpreting of seismic materials. The analysis of geological information (GIS and test results) confirms the approved water–oil contact (WOC) level in the investigated section of the deposit, which makes it possible to recalculate its reserves.

The composition and origin of the Bedenekir Formation deposits of Mountainous Crimea are detailed on the basis of our work results and analysis of both published and unpublished data.

Composition and origin of deposits belonging to Bedenekyr Formation of the Mountainous Crimea based upon generalizations of our own results and analysis of published and unpublished data were specified.

Depositional conditions at the Cenomanian–Turonian time have been specified and a cyclostratigraphic scheme of the correlation of the Turonian sections has been proposed based upon generalizations of our own results concerning sections of Voronezh anteclise, Ulyanovsk–Saratov trough, Crimea, and the Caucasus.

Depositional conditions at the Cenomanian-Turonian time were specified and cyclostratigraphic scheme of correlation of the Turonian sections was proposed based upon generalizations of our own results concerning sections of Voronezh anteclise, Ulyanovsk-Saratov trough, Crimea and the Caucasus.

A stratigraphic scheme for dividing the Triassic–Neogene deposits of the central Crimea by suites has been proposed. The division is based on the generalization of our own results and the analysis of the published and unpublished data.

Two stages are distinguished in the study of Quaternary deposits in Crimea. At the first stage (from the late 19th century to the 1960s), the stratigraphic description of Quaternary strata was based on the allocation of terraced complexes (marine terraces in the coastal part and synchronous alluvial terraces in the continental part of the Crimean Peninsula). At the second stage, the description of Quaternary deposits was based on their climatostratigraphic classification, with the leading role of the loess-soil formation. The structure of the paleo-Dnieper and paleo-Dniester valleys was used as the basis for the stratigraphic subdivision of Quaternary deposits in Crimea. It is shown that the nonlinear reversible changes of the Black Sea level that took place in the Quaternary can break the rule that the lower the hypsometric level of a terrace is, the younger the terrace is.

In the study of Quaternary deposits of the Crimea selected two phases. In the first stage (since the late XIX century to the sixties of XX century) stratigraphic description of the Quaternary strata was based on the allocation of terraced complexes (a marine terraces - in the coastal part and synchronous them alluvial ones - in continental part of the Crimean peninsula). In the second stage description of the Quaternary deposits is made on the basis of their climatic and stratigraphic dissection under the leading role of the loess-soil formation structure. The basis for stratigraphic subdivision of Quaternary deposits of the Crimea was the structure of the valleys of the paleo-Dnieper and paleo-Dniester. It is shown that the nonlinear, reversible character of Black sea level changes that took place in the Quaternary can be broken a rule “the lower the hypsometrically level of the terrace is, the younger this terrace is”.

The Bitak Formation is located in Crimea in the area of the city of Simferopol. It is mainly represented by weakly sorted conglomerates. The lithological description of the conglomerates is given. New data on the age of detrital zircons are presented. The possible age of the Bitak Formation is discussed. It is shown that the Bitak Formation is older than Late Bajocian volcanic rocks and younger than deposits of the Tauric Formation and its analogs of the same age. The Bitak Formation was accumulated in a pull-apart basin. Several basins of such a type are found in Crimea. It is thought that the Bitak basin was located at the base of the Middle Jurassic island-arc complex of Crimea.

Bitak Formation is located within Simferopol area. It is presented by badly sorted conglomerates. Lithological description of conglomerates is given. New data about age of the clastic zircons are presented. The possible age of Formation is discussed. It is assumed that Bitak Formation is older than Late Bajocian volcanic rocks and is younger than deposits of Tavrik Formation ant it analogs. Bitak Formation was accumulated in the pull-apart basin. A few basins of the such type are detected in the Crimea. It is assumed that Bitak basin is located at the base of Middle Jurassic arc-island complex of Crimea.

The results of a complex study of the Upper Cretaceous carbonate section in the quarry of the cement plant of the town of Sengilei (Ul’yanovsk district) are presented. The Lower Paleocene cyclic opoka member is described. The formation conditions of the Upper Cretaceous cyclic and cryptocyclic, as well as Lower Paleocene cyclic, rocks are interpreted for the first time on the basis of lithological, petrographic, petromagnetic, geochemical, and paleoecological methods. The cyclicity was formed due to dilution cycles under climate fluctuation and eustatic variations, which were caused by eccentricity cycles of the Earth’s orbit. These cycles are identified in the cryptorhythmic lanceolata sequence of the Lower Maastrichtian rocks.

Results of the complex research of the carbonate rhythmically bedded section of the cement factory quarry of the Sengeley town of the Ulyanovsk province are presented. Description of cyclically bedded silicious member of Lower Paleocene is presented. For rhythmic and cryptorhythmic Upper Cretaceous and also cyclic Lower Paleocene deposits conditions of it origin by use of a complex of methods including lithological, petrographic, petromagnetic, geochemical, chemical and paleoecological ones, are reconstructed for the first time. Dilution and eustatic cycles, caused by eccentricity cycles of the Earth`s orbit became an agent forming rhythmicity. The last are determined in the cryptorhythmic lanceolata member of the Lower Maastrichtian.

The forming conditions of the cyclic sequence of interbedded clays, marls, and limestones in the lower Campanian Stage of the Kudrino Formation have been studied for the first time by the integrated lithological and geochemical methods. Models for the variations in temperature, salinity, and depth in the Crimean Mountains of the Tethys Ocean in the Early Campanian Age have been proposed.

The sedimentation conditions of Maastrichtian cyclic deposits in the Crimean Mountains were studied in detail for the first time using a complex of lithological and geochemical methods. The models of variations in temperature, salinity, and depth for the Tethys Ocean margin in the Maastrichtian were developed. Summary curves of δ18O and δ13C variations in Maastrichtian deposits of the Crimean Mountains were compiled.

This study presents the first results of the comparison of depositional environments in the Crimean and Caucasian regions of the Crimea-Caucasus trough during the Early Jurassic and Aalenian using lithological and geochemical methods. In this study we proposed new models for variations of temperature, salinity, and bathymetry in the Early Jurassic and Aalenian.

The upper Visean–Serpukhovian strata in the type region for the Serpukhovian Stage is an epeiric-sea succession ca. 90 m in thickness. The predominantly Visean Oka Group (comprising the Aleksin, Mikhailov, and Venev formations) is dominated by photozoan packstones with fluvial siliciclastic wedges developed from the west. The Lower Serpukhovian Zaborie Group is composed of the Tarusa and Gurovo formations. The latter is a new name for the shale-dominated unit of Steshevian Substage age in the studied area. The Zaborie Group is composed of limestones and marls in its lower (Tarusa and basal Gurovo) part and black smectitic to grey palygorskitic shales in the main part of the Gurovo Formation. The Gurovo Formation is capped by a thin limestone with oncoids and a palygorskitic–calcretic palaeosol. The Upper Serpukhovian is composed of a thin (3–12 m) Protva Limestone heavily karstified during a mid-Carboniferous lowstand. The succession shows a number of unusual sedimentary features, such as a lack of high-energy facies, shallow-subtidal marine sediments penetrated by Stigmaria, the inferred atidal to microtidal regime, and palustrine beds composed of saponitic marls. The succession contains many subaerial disconformities characterized by profiles ranging from undercoal solution horizons to palaeokarsts. Incised fluvial channels are reported at two stratigraphic levels to the west of the study area. The deepest incisions developed from the Kholm Disconformity (top of the Mikhailov Formation). This disconformity also exhibits the deepest palaeokarst profile and represents the major hiatus in the Oka–Zaborie succession. The new sea-level curve presented herein shows two major cycles separated by the Kholm Unconformity at the Mikhailov/Venev boundary. The Lower Serpukhovian transgression moved the base-level away from falling below the seafloor so that the section becomes conformable above the Forino Disconformity (lower Tarusa). The maximum deepening is interpreted to occur in the lower dark-shale part of the Gurovo Formation. The base of the Serpukhovian Stage is defined by FADs of the conodont Lochriea ziegleri and the foraminifer Janischewskina delicata in the middle of the sequence VN2. The Aleksinian–Mikhailovian interval is provisionally correlated with the Asbian (Lower–Middle Warnantian) in Western Europe. Based on FODs of Janischewskina typica and first representatives of Climacammina, the Venevian is correlated with the Brigantian in Western Europe. The Tarusian–Protvian interval contains diverse fusulinid and conodont assemblages, but few forms suitable for international correlation. FADs of the zonal conodont species Adetognathus unicornis and Gnathodus bollandensis at several metres above the Protvian base suggest correlation of the entire Zaborie Group and may be the basal Protvian to the Pendleian. Copyright © 2014 John Wiley & Sons, Ltd.

The composition and genesis of the cyclic sequence of Upper Cretaceous sediments near the town of Volsk (Saratov Region) were first investigated using a series of analytical methods. The results were statistically processed using methods of manual counting, as well as spectral and wavelet analyses. Elementary formation cyclites and cyclic variations in several parameters are correlated with astronomo-climatic Milankovitch cycles.

Deposits in the Akhtsu zone have been characterized, with the Mzymta River valley as an example. A lithological-paleontological and geochemical characterization of Callovian-Tithonian deposits has been given. A paleogeographic model has been proposed for the Akhtsu reef, and a chronostratigraphic profile has been established for the Callovian-Albian sedimentary basin in the Easter Black Sea region.

For the first time, a complex lithological-stratigraphic and facial study of the Aptian-Cenomanian sediments of the Abkhazian zone of the Northwestern Caucasus was carried in sections of the Mzymta and Khipsta river valleys. As a result, the areas of distribution of potential oil-source rocks in these sediments, which correspond to the events of the OAE-1 and OAE-2 global paleoecological crises, oil reservoir rocks and rocks-caps were defined.

In this work, based on a well drilled in the valley of the Mzymta River (northwestern Caucasus), the application of the sequence-stratigraphic method is demonstrated in this area for the first time. This method allows us to clarify the nature of numerous repetitions in the same interval of the observed geological sequence (modern, ancient landslide or synsedimentary landslide, and tectonic or eustatic). In addition, the geochemical characteristics of bituminous sediments are reported. The sequence studied in the well shows a complex polygenetic evolution of sediments since Aptian time and the oceanic anoxic event-1 (OAE-1).

For the first time a high-precision planetary stratigraphic correlation of Phanerozoic sedimentary marine and continental deposits on the level of mark beds and members was produced, using a combination of methods of event, paleomagnetic, sequence and cyclic stratigraphy. Schemes of diachronism of biostratigraphic zones for the Late Maastrichtian are proposed.

For the first time the correspondence between engineering-geological elements (EGE) and sequence tracts is established. The sequence-stratigraphic approach allows us to upgrade archival data, determine levels of distribution of solid and weak rocks to predict areas of development of karst cavities and possible slippage of drilling tools, as well as to optimize the sampling process.