Геология

This paper deals with research results of the inocerams from the Upper Cretaceous borehole sections of the Western-Siberian depression. The Lower and Upper Turonian inocerams – Inoceramus (Mytiloides) labiatus Schloth., I. (M.) hercynicus Petr., I. cuvieri Sow., I. lamarcki Woods (non Park.) var II Renng., I. cf. schulyinae Efrem. are described and figured. Questions of the Turonian stage stratigraphy and its dismemberment in France, Germany, USA, Canada and the former USSR are discussed.

New materials on the lithologic composition, character of the boundaries between the subsuites and paleontologic age determinations are presented. Those were obtained upon stydying the well copes from the North of the Don-Medveditsa Dislocations. The data analysis has allowed to divide the depositions in new place of the Volga Region in subsuites. Those are corresponding to standart ammonite zones and peculiar for foraminifer assemblages of their own.

Current reestimation of the stratigraphic positions of some zonal ammonites has resulted in revision of the sequence of ammonite zones, particularly in the Lower substage, and in more detailed stage division. The work has been mainly finished for Central Russia. But it is still in the initial stage in the Volga Region. New data is presented in the paper. Possibility is discussed of compiling an updated biostratigraphic base for dividing the Callovian not only from ammonites, but from foraminifers, as well. 

 In spite of the accepted katagenal laumontite nature from sedimentary strata, its hydrothermal – metasomatic origin in lower-chalky terrigenous deposits,recovering mineral continental rift has been proved. In rocks undergoing propylization of lower temperature, laumontite is a mineral-indicator of containers and calcite-of screens.

The article is about the peculiarities of interference of ground water with massive materials, gases, organic substances, as well as interference of new formations of hydrocarbon fluids with massive materials and waters on the different stages of evolution of aqueous-rocky draws and transformation of the types of geohydrodynamic systems.

New taxa of hexactinellid sponges: Umbrelliserus olferjevi, gen. et sp. nov. (Coeloptychiidae) from the Maastrichthyan of the Volga river basin, Russia and Turbiplana nerodenkoi, gen. et sp. nov. (Leptophragmidae) from the Cenomanian of Ukraine are described. Study of skeletal remains of the described sponges allows to confirm proposed earlier basic trends in morphogenesis of the Upper Cretaceous hexactinellids. It also is evidence of reliability of worked out principles of Cretaceous Hexactinellida systematic on a familial level.

Carbonate nodules have been examined – those forming numerous lenticular chains of diverse lengths at each hypsometric level in the Middle Jurassic deposites. Contrary to the current view of the siderite composition of the nodules, dominant calcite development is proved, with siderite and clay matter involved. The material composition of the nodules is characterized by substantial variations of the component concentrations. Inherent peculiarities of the mineral and of the chemical compositions have been revealed in each suite, alongside with specific textures.

The Gremyachinskoye sylvinite field lies in the south of the Volga monocline, to the northeast of the Severo-Kotelnikovskij overthrust. Halogen beds from the field were examined. The study has provided grounds for correlating the field potassium-bearing horizon with the Pogozhskaya rhythmic member from the Volga monocline. The halogen bed formation was influenced by the principal water area of the salt-generating basin in the east and by the calcium chloride brines discharged along the disjunctive dislocations limiting the overthrust zone.

Problems of modern urban drainage network functioning have been considered. Analysis of geoecological state of separate regions of urban erosive and drawn systems has been carried out. An approach to the optimization of natural and artificial drainage networks has been suggested by the example of Saratov territory. 

The mass extinction of life in the sea and on land 251 million years ago, at the Permian-Triassic boundary, was undoubtedly the largest mass extinction of all time. Sedimentological and geochemical evidence shows that global temperatures rose, that there was extensive oceanic anoxia, and that there was massive erosion of sediment, especially soils, from the land.