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Morphogeneses of the Late Cretaceous Guettardiscyphia (Porifera, Hexactinellida)

Guettardiscyphia skeletons are peculiar for thin walls and highly dense apo- and prosopores. Wall mobility was conductive to formation of conical lobate skeletons of various, occasionally geometrically regular outlines. Substantial number of fossil samples from variously composed rocks from all the Upper Cretaceous intervals has made it possible to trace skeleton transformations in sponge ontogenesis and depending on their environmental conditions.

Hydrothermal Processes in Basement Rocks of the West Siberian Oil and Gas Province

Using Palyanovskoye oil field of Krasnoleninsk arch we demonstrated that local cataclasis and pneumatolytic-hydrothermal metasomatism manifestations are widespread in the Paleozoic basement rocks. For the first time the earliest indications of deep fluid activity were detected – at the stage of granite deep fluid saturation and primary diffuse leaching of feldspars. During transition to the infiltration process, they comprise jet-stream fibroblast structures formed due to biotite and plagioclase resorption by amphibole and scapolite association.

Bio-, Magneto and cyclostratigraphy of upper Berriasian near v. Alexeevka (Belogorskiy Region, Republic of Crimea). Article 1. Ammonites. Magnetostratigraphy. Cyclostratigraphy

The results bio-, magnetostratigraphic, cyclostratigraphic, lithological and mineralogic studies of the upper part of Sultanovskaya formation and Zelenogorskaya formation near v. Alexeevka (Belogorskiy region of Crimea) were presented in current work. The results of lithological and mineralogic analysis argues for the stratigraphic break between “Sultanovskaya” formation and “Zelenogorskaya” formation and implicitly indicate the age of the sediments as late berriasian.

Definition of Paleointensity in the Eocene Section Plateau Aktolagay

There was explored the behavior of Rns parameter (relation between the module of natural remaining magnetization after temperature 250° to the magnetization of saturation) in the interval of Ypresian in Aktolagay plateau (West Kazakhstan). The parameters were recounted to the values of H/H0 (relation between paleointensity to the intensity of modern magnetic field).

Permian and Triassic Fish Holotypes Kept in the Earth Sciences Museum at the Saratov State University. Article 2. Actinopterygian Fishes

The paper presents the first holotype review of all the known Permian and Triassic ichthyofauna taxa of the Actinopterygii class, recognized and described by the researchers from the Saratov State University starting from the 1960-ties and currently kept at the University Earth Sciences Museum. Among the previously unknown taxa, there are two orders, three families, 22 genera and 57 species of actinopterygian fishes. Data on taxonomic compositions is provided, holotype numbers are presented alongside with their geographic and geologic referencing.

Peculiarities of Compositions and Formation Environments of Potassium and Potassium-Magnesium Rocks From the Pogozhskaya Rhythmic Member in The Northwestern and the Northeastern Parts of the Caspian Slope Zone

The paper presents the results of composition examination of the uppermost of the Pogozhskaya rhythmic member from the northern near-slope fringes of the Caspian Region. The potassium-bearing horizon encountered there is determined to have resulted from the demineralization stage overlapping the carnallite and the bischofite stage deposits. In potassium salt accumulation, the major importance is attributed to the process of potassium ion concentration during the large-scale precipitation of salt-out halite associated with inflowing brine condensed to halite stage.

Results of Application of the Oil and Gas Potential Preliminary Assessment Exploration Technology over the Potential Area of Saratov Region

To improve the efficiency of geophysical prospecting, the Department of Geophysics of the Faculty of Geology of Saratov State University develops original complexation technology allowing to evaluate the possibilities of identifying promising oil and gas areas by circular thermal-magnetic anomalies, limited to the gradient zones of areas of gravimagnetic complex parameter or geopotential fields anomalies itself. The article presents the experience of applying non-seismic elements of the complex of this technology.

Features of Postsedimentation Alteration Sand Accessory Mineralization with in Rocks at Final Stages of Halogenesis in the Outer Slope Zone of the Caspian Depression

The paper deals with regularities of postsedimentation changes in rocks at the halogenesis final stages within the Gremyachinskoye potassium salt field. Relation ship has been revealed among the postsedimentation processes, brine composition peculiarities, structure and regularities of terrigenous material inflow. Substanti al role of partial metasomatic replace mentofsalting-out halite in carnallite rocks is specified, as well as the role of diagenetic processes in halogen series, frequently accompanied with initial phases of plicative deformations.

The Matrix Method for Solving the Problem of the Second Kind Seismoelectrical Effect in a Geological Medium Biot

The matrix method for solving the problem of Seismoelectrical effect of the second kind is suggested. The excitement of this effect in a horizontally-layered medium by a point source of mechanical vibrations is considered. An analytical solution of the problem of the second kind Seismoelectrical effect for a homogeneous space is obtained.

Forecast of the Phase State of Hydrocarbon Deposits in the South-East of the Volga-Ural Province

In article modern geothermal conditions of the main oil-and-gas complexes are analysed, temperature and deep borders of change of a phase condition of deposits of hydrocarbons are revealed, сonclusions are drawn on a possibility of the separate forecast of deposits of fluids, various on structure, in the considered territory.

Representatives of the Genus Camerospongia (Porifera, Hexactinellida) from the Cenomanian in the Volga Region

The earliest assemblage of Cretaceous sponges has been found in the Cenomanian terrigenous rocks (the Melovatka suite) from the south of the Volga right bank region. A noticeable element of the assemblage is composed of small-sized Camerospongia, newly recognized in the region and peculiar for forming monotype colonies as well.

Features of Mineral Composition North Shchigry and Rogowski Diorite-granodiorite Arays of Kursk Block (Central Russia)

North Shchigry and Rogowski diorite-granodiorite arrays are intrusive shtok bodies. As part of the intrusions of rocks studied potassium feldspar, plagioclase, hornblende magnesia, phlogopite, muscovite, quartz, and epidote.

Morphotypes of the Late Cretaceous Hexactinellids (Porifera, Hexactinellida)

Basic structure types have been specified in hexacinellids with soldered spicule lattice. The fossils of those occur as skeletal forms. Certain tendencies in Lychniscosa and Hexactinosa morphogenesis were identified as conductive to shaping the spectrum of skeleton archetypes. The increase of sponge morphological diversity was in many ways predetermined by thickness reduction of the skeleton-forming walls, associated with reduction of the irrigation system elements. That has brought about forms of complicated tubular labyrinth habits.

Localization of the Anomalies of Geopotential Fields on the Basis of the Frequency and Correlation of Change

The considered methods of separation of gravity and magnetic anomalies in order to distinguish the local search objects. Shows the examples of practical application of these techniques.

Rhenium in the Volzhsky Stage Deposits of the Volga Shale Basin Central Part

Multibillion oil shale resources within the Volga shale basin central part (Privolzhsky Federal District: Samara, Saratov, Ulyanovsk, and Orenburg regions) are low-quality sulfurous mineral raw materials. The commercial rhenium content in oil shale was found in the randomly selected samples from the Kashpirsky, Orlovsky, Perelyubsky, and Kotsebinsky fields. Rhenium concentration varies from 0.013 to 0.22 g/t with the ore marginal commercial concentration (as a concomitant component) of 0.05 g/t.

A New Species Actinopterygian from the Upper Permian of Moscow Syneclise

A new species actinopterygian fish Isadia opokiensis sp. nov. (Eurynotoidiidae, Eurynotoidiformes) of the Late Permian from Moscow syneclise are described.

Integrated bio and Magnetostratigraphic Study of the ≪Ozerki Sections≫ (Upper Cretaceous, Right Bank of the Volga in the Saratov Region). Paper 1. Section Characteristics, Results of Petromagnetic and Magnetic-mineralogical Examinations

In the right-bank part of the Saratov Region, a section of terrigenous and carbonate rocks has been determined to underlie the ≪sponge≫ horizon conventionally dated back to the Santonian. The maximum thickness of the marls, constituting a substantial portion of the section, occurs in the western part of the region. Field description is presented alongside with the correlation scheme of the recognized stratified intervals in the three joined Ozerki objects and the results of petromagnetic and magnetic-mineralogical examinations in the carbonate rock interval.

Experience of Cyclostratigraphic Analysis of Petromagnetic Data on the Turonian–Maastrihtian Section «Nizhnyaya Bannovka» (Volga River Right Bank, Southern Saratov Region)

On the base of spectral Fourier analysis of magnetic susceptibility time series of nearly 10 000 measurements of rock samples in the turonian-maastrihtian sediments, exposed near Nizhnyaya Bannovka village (Volga River Right Bank, Southern Saratov Region) there were detected long and short eccentricity cycles. Petromagnetic variations, correlated with different variants of eustatic curves detected the presence of well known sequences. The study includes the calculations of sedimentation rates, localization of sedimentation breaks and estimation of their duration.

Geochemical Characteristics of Oil Shales in the Volzhskii Basin and Productive Forecast of Rhenium Commercial Concentrations

This article is about geochemical characteristics of oil shales in the Volzhkaia oil shale formation. Tendency of changing of TOC, REE and biophile elements has been examined laterally and vertically based upon cross cuttings of Perelubskoe and Kotsebinskoe developments. Possible interrelation between concentration of molybdenum and rhenium in the Volzhskii basin has been discovered. Intervals of ash material and their potential genesis have been closely considered.

Module Organization in the Late Cretaceous Hexactinellids (Hexactinellida, Porifera)

Knowledge on the regularities of vegetative propagation and comprehension of the osculum (oscula) and subosculum structural-functional positions and interrelations in the skeleton structure have made it possible to specify the organization levels in the Late Cretaceous hexactinellids: the unitary (solitary, perifrontal and autonomous forms), transitory (solitary, autonomous and colonial forms) and colonial (primary and true colonies) ones.