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Current problems in the North Caspian depression geology and oil and gas prospects

The deep structure and formation of the North Caspian (Precaspian) depression have not been fully understood due to the scarcity of depth studies at 18–22 km. The existing concepts and hypotheses are clearly insufficient to interpret the unexplained facts. New approaches and research efforts are necessary to solve the old problems. The current state of the depression deep structure problems is reviewed, and the existing explanation flaws are demonstrated. The depression consolidated crust has oceanic and riftogenic origin as it has been suggested by the author before.

Cygnus from the late pleistocene of Bingadi asphalt deposits of Azerbaijan

Two species of Cygnus from the Late Pleistocene deposits of Binagadi asphalt lake are described in this paper, which have not been previously known from this locality. Cygnus cygnus is represented by the left distal fragment of the radius; the right fragment of the proximal humerus and ulna belongs to Cygnus olor. Morphological analysis with recent and fossil species of the genus Cygnus makes it possible to establish taxonomic differences between species, based on certain diagnostic features that can serve as criteria for identifying species.

Lithological and petrophysical characteristics of the deposits of the Vogulkinskaya strata within the maly Teterevsky shaft (Shaimsky oil and gas region)

Study results of the material composition and conditions of forming P Vogulkinskaya strata of the Tolumskoye field are presented. It is established that the formation of sediments occurred in coastal-marine conditions, in the transgressive stage of the sedimentation basin development. According to the composition of the allotigenic part, the studied sandstones and siltstones correspond to the quartz, grauwack and arkose groups.

Pseudoderivations of Paracraticularia cylindrica (Michelin, 1840) (Porifera, Hexactinellida)

The morphological diversity of diosculumic sponges, known as Paracraticularia cylindrical, results from the fact that many fossils assigned to this species prove to be fragments of the apical segments of internodes (branches) from major colonies that are rarely encountered as totally preserved fossils. The structures of the branch apical segments and the oscula outlines reflect various manifestations of hexactinellida synchronous division conductive to morphological diversity of the descendants, the succeeding complicatedly structured colonial sponges.

Conditions for the formation of deposits in the upper part of the Berriasian section near v. Alekseevka, Belogorsk region, Republic of Crimea

The results of the paleoecological analysis on ostracods of the upper part of Sultanovskaya Formation (Boissieri zone) in the section near v. Alekseevka are presented. Five ostracod assemblages reflecting changing conditions in the paleobasin are defined. It was established that the sedimentation in the Late Berriasian time occurred under conditions of a warm normally salty with a calm hydrodynamic regime of the basin, mainly in oxygen waters.

Natural conditions of the Popigai diamond deposit (North-West Yakutia)

The article highlights the features of the diamond mining industry in Yakutia. The history of the discovery and study of impact diamonds Popigai deposit formed as a result of the penetration of the eponumous huge meteorite into the rock mass are traced. Some features of Popigai crystals and the prospects of their use in various sectors of the national economy of the country are characterized.

Results of the reconnaissance magnetostratigraphic studies of Paleocene in the southern part of the Saratov right bank

The results of rock-magnetic and paleomagnetic studies of two sections of the Lower Syzran subformation (Paleocene) of the Saratov Right Bank – the Syrt Mountain (Nizhnyaya Bannovka village) and Lysaya Gora (Saratov city) are presented. For the first time the possibility of obtaining paleomagnetic data on the Paleocene of the Volga region and their use for magnetostratigraphic purposes despite the partial remagnetization of rocks has been established.

Nannopterygius finds in the West Kazakhstan region of the Republic of Kazakhstan

This article describes the skeletal fragments of new species of ichthyosaurus Nannopterygius mikhailovi sp. nov. and Nannopterygius yakimenkae sp. nov. from the Upper Volga sublayer of the Upper Jurassic of the West Kazakhstan region of the Republic of Kazakhstan (Shchuchkino section). The species are assigned to the genus Nannopterygius.

A new locality of chondrichthyan fishes from the Upper Paleocene on the right bank of the Don river (Volgograd region)

An assemblage of chondrichthyans is described from the new locality near Serafimovich town (the western part of Volgograd region). More than 2500 fossils were collected from the basal gravel-pebble bed and phosphorite-bearing layer from the lower part of the Buzinovka formation (upper Paleocene). There are reworked Cretaceous and Paleocene chondrichthyans (6 species) and synchronous 21 species of sharks and 2 species of chimaeroids.

New data on the Late Permian actinopterygian fish Toyemia Minich, a zonal genus of the Permian biostratigraphic scheme based on ichthyofauna from the Eastern Europe

The structure of the actinopterygian fish genus and speciesToyemia tverdochlebovi Minich has been completed for the first time using a previously unknown complete skeleton and skeletal fragments from Late Permian localities of Eastern Europe. The structure of a head which so far remained unknown in the genus is described. The dorsal fin location far from the head near the caudal region was confirmed as expressed earlier by the taxon’s author.

Deep meridional structures of the East-European platform

Using a complex of remote and surface geophysical methods in the eastern part of the East European Platform, regional meridional heterogeneities were revealed; it is shown that these heterogeneities can be caused by low-density and magnetically active rocks in the crystalline crust and mantle. The totality of geological and geophysical data indicates the relationship of meridional heterogeneities with transcontinental deep faults.

Representatives of the Subfamily Cheloniceratinae Spath, 1923 (Ammonoidea)from the Aptian of Mangyshlak, Western and Southern Turkmenistan. Paper 1. General Issues. The Genus Cheloniceras Hyatt, 1900

The article presents the study results of the ammonite subfamily Cheloniceratinae Spath, 1923 representatives (genera Cheloniceras Hyatt, 1900 and Epicheloniceras Casey, 1954) fromthe Lower and Middle Aptian of Mangyshlak, Western and Southern Turkmenistan. The diversity and stratigraphic distribution of species is assessed, intraspecific variability is identified and typified. Representatives of the genus Cheloniceras are described.

Multi-feature petrophysical classification of rocks as a basis for interpretation of geophysical data

The work is carried out approbation of the algorithm for the complex interpretation of geophysical data using data classification algorithm. Distributions by class are obtained and compared with petrophysical materials from published sources. This data is compared and geological composition of the studied area is obtained. The applicability of this approach for the integrated interpretation of geophysical data is shown, including low-level studied areas with a complex geological structure.

On the question of the geological nature of the crystalline basement inhomogeneities of the East European Platform

Based on the analysis of gravitational and magnetic anomalies of the eastern part of the East European Platform, it is concluded that inhomogeneities caused by serpentinization processes are present in the Earth’s crust. This conclusion is confirmed by conducting geological and geophysical studies on reference objects with serpentinite outcrops.

The biogenic component of the Middle Turonian phosphorite horizon from the Senomanskaya Stenka section. Paper 1. Materials and paleoecological analysis

The paper analyzes the taxonomic composition and the habitat of the representatives of the Middle – Late Cenomanian and the Middle Turonian marine biota. The examined fossils have been isolated from the bulk sample obtained from the phosphorite horizon lying in the bottom of the Middle Turonian carbonate rocks in the Senomanskaya Stenka section (Volgograd Region, Zhirnovsk district). 

Representatives of the subfamily Cheloniceratinae Spath, 1923 (Ammonoidea)from the Aptian of Mangyshlak, Western and Southern Turkmenistan. Paper 2. The Genus Epicheloniceras Casey, 1954

The representatives ofthe genusEpicheloniceras Casey, 1954fromthe Middle Aptian of Mangyshlak, Western and Southern Turkmenistan are described.

Paleogene quartz sandstones of the Sosnovka Formation of the Uljanovsk-Syzran Volga region (Eastern Russian Platform): Mineral composition and origin

The Paleogene quartz sandstones of the Sosnovka formation are widely occurred in the Uljanovsk-Syzran Volga region and are used as valuable building materials. The article comprises an improvement for the continental origin of the Sosnovka sandstones based on the results of a comprehensive study of the features of the mineral composition and microstructure of quartz sandstones of the Sosnovka formation obtained by using petrographic, XRD and electron-microscopic analyses.

The biogenic componentof theMiddle Turonian phosphorite horizonfrom the Senomanskaya Stenka section. Paper 2. Biostratinomical analysis

The paper presents biostratinomical characteristics of the Cenomanian and the Turonian fossil complexes found in the Middle Turonian phosphorite horizon from the Senomanskaya Stenka section (Volgograd region, Zhirnovsk district) constituting the basis of the benthic colonies and nekton communities. Probable interpretations for the settings contributory to generation of the phosphorite inclusion clusters are provided.

Colonial Leptophragmidae (Porifera, Hexactinellida) from the Lower Santonian of the Volga region

Study of the skeletal morphology of a new representative of the Leptophragmidae family, with no suboscula in its structure, provides support for the earlier specified regularities in generation of Hexactinellida modular forms. Good preservation state of a major colony has made it possible to specify the aspects of paleoecology and taphonomy in the later representatives of the Middle Coniacian – Early Santonian succession of siliceous sponges.

The results of the probabilistic correlation analysis of geological and geophysical data on the territory of the Scythian and Pre-Caspian morphological structures to assess the prospects of oil and gas-bearing areas

The article considers method application results of correlation analysis of gravitational and magnetic field data, heat flux values, data of decoding satellite images measured in the regions of the Pre-Caspian and Scythian large concentric morphological structures of the central type. As a result, using the correlation method, a complex of various geophysical fields in these regions was analyzed. Local concentric morphological structures with high values of the gravitational field and heat flow promising for the search of new oil and gas fields were identified.