The spectrum of EG UMa

Spectra and radial-velocity curves for the precataclysmic variable EG UMa are analyzed. The system ephemeris has been improved and all system parameters determined. The parameters of the secondary are consistent with current evolutionary models for single main-sequence M stars with atmospheric metallicities exceeding the solar value by 0.5 dex. We have verified that the rotational velocity of the red dwarf exceeds the velocity corresponding to synchronous orbital motion by a factor of two to three. This suggests that the efficiency of tidal interactions between the components in the synchronization of their motion is low. The observed Ca II emission lines display reflection effects in a number of uniform spectra of EG UMa obtained during the quiescent state of the secondary.     

Seismic stratigraphy of the Upper Quaternary deposits on the northeastern slope of the Ceará Rise (Central Atlantic)

This study is focused on interpretation of ultrahigh-resolution seismoacoustic data from the northeastern slope of the Ceará Rise (Central Atlantic) acquired using the SES 2000 deep parametric narrow-beam subbottom profiler during cruise 35 of RV Akademik Ioffe in 2011. The geologic nature of most of the detected reflectors is constrained by correlation of the results of seismoacoustic profiling with core data collected in frame of the Ocean Drilling Program (ODP site 929A-E). Detailed seismostratigraphic study of the Upper Quaternary deposits in the study area has implications for better understanding of the role of gravity flows and bottom currents in sedimentation on the NE slope of the rise for the past 1.2 Myr.     

Fractionation of Rare-Earth Elements in the Processes of Hydrothermal Ore Formation

The data on the distribution of elements in the Pb–Zn cross-section of the Gatsirovskaya vein (the Upper Zgid deposit, North Ossetia, Russia) have shown that the spectra of rare-earth elements (REEs) changed significantly in the ore samples during the vein formation. The sharp growth of the La_N/Yb_N, La_N/Nd_N, Gd_N/Ho_N, and Gd_N/Yb_N ratios is confined to the vein intervals, where the maximum amount of ore components is deposited. The comparison of the REE spectra of ores to the characteristics of the spectra of the rocks surrounding the vein and the host rocks suggests that the vein material deposited from the solutions in which the REE ratio changed with time. REE fractionation occurred due to the mobilization of components by hydrothermal solutions during their interaction with the Paleozoic host granites.     

Multidisciplinary Investigation of the Transform Fault Zones Doldrums and Vema during Cruise 45 of the R/V “Akademik Nikolaj Strakhov”

Oceanology - Herein we provide information on the integrated geological, geophysical, sedimentological, paleoceanographic, hydrophysical and biological investigations in the Central Atlantic during...     

Investigation of the Modern Lateral Sedimentation on the Argentine Continental Slope during Cruise 79 of the R/V Akademik Mstislav Keldysh

Oceanology - Herein we provide information on the sedimentological and paleoceanographic research on the Argentine Patagonian continental slope during cruise 79 of the R/V Akademik Mstislav Keldysh...     

Results of the First Year of the 3BS Polar Search Program

Astronomy Letters - We present the results of the first year of searching for polar candidates within the 3BS (3-Band Survey) program using medium-band filters. Observational data for 84 selected...     

Correlation between temperature and salinity variations as a characteristic of the North Atlantic waters

Based on the data of deep-ocean ship observations of temperature T and salinity S, analysis is carried out of the fields of pair correlation coefficients between T and S at different depths as an additional characteristic of water masses in the layer 0–1000 m in the North Atlantic. As a result of analysis, surface, subsurface, and the upper part of North Atlantic intermediate waters are classified according to a degree of correlation between temperature and salinity. The emphasis was given to regions with low correlations, because they indicate the prevalence of the interaction processes that differ most from the typical mixing of two water masses with entirely different characteristics.