Age of Detrital Zircons from Sandstones of the Mesozoic Flysch Formation in the South Anyui Suture Zone (Western Chukotka)

The South Anyui fold zone (western Chukotka) is considered a suture zone related to closure of the South Anyui oceanic basin and collision of Eurasia with the Chukotka–Arctic Alaska microcontinent in the Early Cretaceous. The existence of a compensatory sedimentation basin (foredeep) during folding in the terminal Jurassic–initial Cretaceous remains debatable. This work presents first data on age estimates of detrital zircons from Upper Mesozoic terrigenous sequences of the South Anyui suture zone obtained by the fission-track method. The distal flysch of presumably Late Jurassic age and the proximal flysch of probably Late Triassic age were sampled in the Uyamkanda River basin. The fission-track dating showed that sandstones from the flysch sections contain detrital zircons of two different-age populations. Young zircon populations from sandstones of distal turbidites in the upper course of the Uyamkanda River (two samples) are 149 ± 10.2 and 155.4 ± 9.0 Ma old (Late Jurassic), whereas those from coarse-grained proximal turbidites sampled in the lower course of the Uyamkanda River (one sample) is 131.1 ± 7.5 Ma old (Early Cretaceous). The data obtained indicate that the Late Mesozoic folding in the South Anyui suture zone was accompanied by the formation of a marginal sedimentary basin. Sediments accumulated in this basin compose tectonic nappes that constitute a fold–thrust structure with the northern vergence.     

N and C Isotopic Compositions of the Lower Triassic of Southern Primorye and Reconstruction of the Habitat Conditions of Marine Organisms

N and C isotopic data are recorded and presented for the first time for the Lower Triassic claystones of Southern Primorye (Abrek Section). Five N isotope intervals and 11 more or less pronounced negative C isotope excursions, likely to reflect instability of the temperature regime and the oceanographic situation in the Early Triassic, are recognized in the section. The most favorable conditions for ammonoid recovery and other marine organisms in the Early Triassic (after the end- Permian ecological crisis) were associated with the late Induan—early Olenekian transgression and probable cooling.     

Territorial zoning for the purpose of reforestation from changes of total ozone content in the atmosphere (exemplified by the Tomsk region)

Based on analyzing and forecasting the reconstructed changes of total ozone content (TOC) in the atmosphere over the Tomsk region, two zones of its changes are identified. It is shown how the capacity for survival of conifer transplant stock can be enhanced on the basis of territorial zoning from TOC changes by varying the time and place of planting.     

On the equilibrium figures of an ideal rotating fluid in the post-newtonian approximation of general relativity

A stability criterion is given for the equilibrium form of an ideal rotating fluid in the post-Newtonian approximation. This generalizes the known Lyapunov criterion in classical dynamics. The sphere stability is also investigated and it is shown that it is stable only whenR>22.2R _g (R is the relativistic sphere radius,R _g the Schwarzschild radius).     

Experimental Study of the Formation of Chromium-Bearing Priderite and Yimengite as Products of Modal Mantle Metasomatism

Doklady Earth Sciences - The results of experiments on the synthesis of exotic titanates (priderite and yimengite) simulating metasomatic conditions of alteration of the mantle minerals (chromite...     

Asymmetric outgassing of short-periodic comets with respect to perihelion

The asymmetric model accounting for nongravitational effects is applied to improve orbits of a number of short-periodic comets that have shifts of maximum brightness with respect to their perihelions. Shifts of maximum gas productivity have been obtained for 20 short-periodic comets using photometric and dynamic methods. When using the photometric method, the maximum gas productivity is supposed to coincide with the maximum brightness of the comet, while, in the dynamic approach, it is believed to correspond to the maximum nongravitational acceleration. An analysis and evaluation of the results have been carried out.     

“In situ” visualization of phase states and transformations of hydrocarbons in water-oil mixtures at high and ultrahigh temperatures and pressures

Doklady Earth Sciences -     

Analysis of volcanogenic perturbations of the subarctic ozonosphere on the basis of space monitoring data

The response of the total ozone (TO) at subarctic latitudes to volcanic eruptions, products of which were injected into the stratosphere, is analyzed. It is established that the behavior of the series of average annual TO values according to the TOMS, SCIAMACHY, and GOME space equipment data averaged for 55°–65° N latitudes agrees with the activity of explosive volcanic eruptions. The series of the TO satellite monitoring instrumental data are extended by 200 years into the past using a reconstruction from the dendro-chronologic data. An analysis of the series of TO reconstructed values indicates that volcanogenic perturbations of the subarctic ozonosphere initiate long-term negative TO deviations. In this case, the TO negative deviation depth depends on the frequency of the ozonosphere volcanogenic perturbations and the phase of quasiperiodic oscillation cycles rather than on the strength of a single volcanic explosion.