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Using the solution of a closed problem of the theory of plasticity some analytic expressions were obtained for determination of the strain parameters of zone of deformation in view of the temperature factor. more...

A review of data on sources and sinks of hydrogen of various origins in the atmosphere and in the near-surface part of the earth's crust is given (in some cases we are talking about the crust as a whole). Based on the results of the consideration of this information, it was concluded that the influence of underground non-biogenic ("geological, (white)") hydrogen on the content and balance of gas in the atmosphere, up to the stratosphere, is insignificant. The complexity of the experimental determination of the flow of geological hydrogen, free of biogenic and anthropogenic interference, the influence of the testable excavation, etc. is obvious. Probable sources of deep hydrogen are considered: the remains of magmatic gases (outside the areas of volcanism), metamorphic reactions, and radiolysis of water. The possibility of significant H2 export is evident only in currently activated fault zones. The data on the most powerful suppliers of geological hydrogen - modern active volcanoes and thermal fields - are given. The gas circulation scheme of the Avacha volcano is built, based on the thermal model. The latter is controlled by data from geothermometers, the results of direct temperature measurements in deep wells, and a velocity model. The possibility of fumaroles carrying unchanged hydrogen from the magma chamber has been shown. The prospects for the formation of hydrogen deposits are assessed as uncertain. Magmatic and metamorphogenic gas in some areas is formed enough to accumulate a significant deposit over several tens of thousands of years. But the possibility of its preservation during this period or longer raises doubts. Hydrocarbon deposits without material input from great depths can lose reserves in much less time. Higher rocks' permeability to hydrogen contributes to much greater gas leaks. [ABSTRACT FROM AUTHOR] more...

The paper presents a new understanding of the geologic composition and geodynamic evolution of the Mongol-Okhotsk Fold Belt. It considers the issues related to recognition and substantiation of the Amur composite microcontinent (Amuria superterrane). We analyze the latest data on the geologic composition, age, and paleomagnetism of the Neoproterozoic-Paleozoic complexes, such as the Argun terrane and neighboring structures of Transbaikalia and Mongolia, as one of the key elements of Amuria. In particular, we have refined the age of a number of Precambrian and Paleozoic stratified and magmatic stages and demonstrated the absence of an Archean-Paleoproterozoic crystalline basement. Using a set of our own paleomagnetic and paleontological data, we have substantiated the equatorial position of the Argun terrane in the close proximity to Siberia at 560-525 Ma. The results of our study and the performed analysis of available geological data on the Argun terrane and neighboring Transbaikalia and Southeastern Asia territories point to the fallacy of previous arguments about the Amur composite microcontinent as a single tectonic unit, whose collision led to the formation of the folded structures of the Mongol-Okhotsk belt. This conclusion is of crucial importance for reconstructing the geodynamic evolution of the eastern part of the Central Asian Fold Belt in the Neoproterozoic, Paleozoic, and Mesozoic. [ABSTRACT FROM AUTHOR] more...

Petrological and geochemical studies performed with invoking data on the compositions of clinopyroxenes have clarified the conditions of formation of Vendian-Cambrian basaltic complexes in the Dzhida zone of the Paleoasian Ocean (northern Mongolia and southwestern Transbaikalia). The research was based on a comparative analysis with reference igneous basaltic associations. Of special importance are our microprobe data on trace and rare-earth elements in clinopyroxenes from igneous rocks of different present-day geodynamic settings, namely, N-MORB (Mid-Atlantic Ridge, Central Atlantic), OIB (Bouvet Island, South Atlantic), WPB (within-plate tholeiitic plateau basalts of the Siberian Platform), and boninites of ensimatic arcs (Izu-Bonin island arc, Pacific). The studies have shown that the paleo-oceanic structures in the district of the Urgol guyot formed during geodynamic processes under the impact of mantle plumes on oceanic spreading crust, which resulted in oceanic basaltic plateaus and within-plate oceanic islands. All these structures were later superposed by typical island-arc structure-lithologic associations. Formation of basalt complexes in the Dzhidot guyot district proceeded with a stronger effect of enriched plume melts of within-plate oceanic islands as compared with the Urgol guyot. This is evidenced from petrochemical and geochemical data showing the development of OIB-type magmatic systems on the oceanic basement. Data on clinopyroxenes confirm the participation of mantle plume in this process, which led to the evolution of magmas from typical oceanic basalts (MORB) to plateau basalts and OIB. [ABSTRACT FROM AUTHOR] more...

Incorporation of transposone Tnl of ampicillin resistance into the chromosome of E. coli C600 resulted in formation of at least 8 types of auxotrophic mutants. The transposone incorporates mainly into the loci the damage of which induces proline deficit (20 per cent). The sites of incorporation of transposone Tnl in the chromosomes of E. coli C600 and E. coli JC411 did not coincide. more...

Insertion of transpozone TnI determining ampicillin resistance into the E. coli K-12 chromosome resulted in formation of auxothrophic mutants of 2 types. The mutants of the first type carried thermosensitive mutation resulting in auxotrophy with respect to isoleucine at a temperature of 43 degrees C. Such mutants occurred with high frequency (up to 14 per cent with respect to the number of the survived cells with the chromosomes carrying inserted TnI) and had capacity for reversion to the phenotype of the wild type. The mutants of the second type occurred with a frequency 20--180 times lower than that of the mutants of the first type and did not reverse to the phenotype of the parent bacteria. It was found that the chromosome of E. coli K-12 possessed at least 7 sites available for transpozone TnI insertion. more...