The dynamics of changes in the species diversity of
radiolarians during the last 150 million years with
accuracy to one geological century was determined.
The basic patterns of species and taxa of high rank
change had been established for the boundary
between Cretaceous and Paleogene. There were
revealed topomorphic features of bipolar species,
which have succeeded from the Cretaceous into the
Paleogene and became ancestors of Cenozoic
radiolarian fauna. Changes in the species number in
the boundary between Cretaceous and Paleogene
periods, and also significant variations in the species
diversity in Paleocene and Eocene are connected to a
combination of a number of factors. The most
important of those factors are geological processes,
causing extensive transgressions and regressions,
climate variability, the overall evolution direction of
the Earth biota and competition for important
chemical components for the Radiolaria’s livelihood.
The emergence of powerful tropical forests on the
land with their huge bio-production and bio-chemical
erosion is connected to late Cretaceous era. This
resulted increasing of the dissolved material
proceeding into the sedimentation pool, what is
confirmed by classical bauxites emergence. Because
aluminium oxide and silicon oxide are geochemically
connected, we can state as well about
increasing of dissolved silica flow initiated
development of Diatoms, which became competitors
to Radiolaria in their battle for silica. The last ones
are lost this battle, what caused the species
decreasing. That was not a catastrophic event with
immediate extinction, but a long process
The studies of synthetic sand deposits formed after working dredges deposits in river valleys, have established significant heterogeneity of filtration properties of elementary layers of sand of different grain size distribution. The features of the structure of the array of man-made structures provide a large capacity of absorption of suspended clay particles and the conditions for water purification by adsorption
This article discusses results of hydrogeological study including morphometric terrain analysis of irrigation systems of Syrt Plain. The author of this article tries to prove that irrigation of chestnut soil in Syrt Plain can be achieved without employing regular drainage systems by citing the example of long-term irrigation system employed by experimental station in the town of Ershov
The article presents the evaluation of geotechnical conditions of gypsum Bogomolovskoye deposit, the Perm Region. It is shown, that the main influence on the conditions of the development of the field will have surface and underground karst
The original soils were investigated at the Black Sea coast of Russia. Severe degradation of the soil in a Utrish nation reserve were identified as a result of high recreational pressure. Soils with high recreational load have low humus content (2-3 times) and a lower en-zymatic activity than the control of the soil. Biological parameters can be successfully used for environmental monitoring of soil of Utrish reserve, in contrast to the chemical and physic-chemical properties
Climatic conditions have considerable impact on biological properties of soils of the South of Russia. From all studied indicators the most dependent on climate there was maintenance of a humus and activity of polyphenoloxidases and peroxidases. Values of the integrated indicator of a biological condition (IIBC) on a profile of soils decrease in process of increase in an amount of precipitation, decrease in temperature, and increase in height of the district in next order: meadow
subalpine → brown forest → gray forest → black leached soil → black typical soil → black ordinary soi
In West Karelia (Severny Prigranichny locality), an extension of the Hattu greenstone belt (Finland) was traced and diorite-tonalite and granodiorite complexes, similar in petrochemical characteristics to the Kuittila and Viluvaara complexes, and near-N-S-trending shear-zones, favourable for gold concentration, were revealed. Gold is most likely to occur in Kadilampi-type massives, in schistosity and silicification zones in them and in their haloes. Gold ore occurrences and mineralization points, such as Kadilampi, Kuslokki, Gornoye, Soluha, Kappala and some others, were located
The article summarizes the main factors of regional engineering and geological conditions, and the results of zoning on the basis formation analysis and classification of engineering-geological conditions in the Perm region
In this article we have analyzed the geological structure of the deposit; thickness of stripping soils, ore, sub-standard layers and cavernous rocks were estimated, made estimation of reserves and given the qualitative characteristics of the ore
In this article, the tectonic framework of terrain of construction of a railway tunnel №6 is considered: mated automobile and railway Adler – Alpika – Ser-vice mountain-climate health resort. Endogenic allocation of a fracturing in a rocky block in directions and a density function on a block is learnt in details. The fracturing assaying on reference stages has demonstrated all spectrum of allocations of the basic linear flaws and the loosened bands