Identification of hydrogeological windows based on large-scale mapping of the geological and hydrogeological conditions in Moscow

An original procedure for mapping hydrogeological windows is based on studying the geological structure of the massif overlaying the Podol’sko-Myachkovskii aquifer, changes in the hydrodynamic and hydrogeochemical conditions in the zone of “windows”; as well as calculating the travel time of contaminants in the vertical flow from the Meso-Cenozoic to Podol’sko-Myachkovskii Carboniferous aquifer. Both the areal and vertical distributions of low-permeability deposits are taken into account along with the variations of their thickness and permeability. The results obtained can be used in the development of groundwater protection measures and economic activity regulations in areas with hydrogeological windows.     

Analysis of the optical emission of the young precataclysmic variables HS 1857+5144 and ABELL 65

We analyze the physical state and the properties of the close binary systems HS 1857+5144 and Abell 65. We took the spectra of both systems over a wide range of orbital phases with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) and obtained their multicolor light curves with the RTT150 and Zeiss-1000 telescopes of the SAO RAS. We demonstrate that both Abell 65 and HS 1857+5144 are young precataclysmic variables (PV) with orbital periods of P _orb = 1. ^d 003729 and P _orb = 0. ^d 26633331, respectively. The observed brightness and spectral variations during the orbital period are due to the radiation of the cold component, which absorbs the short-wave radiation of the hot component and reemits it in the visual part of the spectrum. A joint analysis of the brightness and radial velocity curves allowed us to find the possible and optimum sets of their fundamental parameters. We found the luminosity excesses of the secondary components of HS 1857+5144 and Abell 65 with respect to the corresponding Main Sequence stars to be typical for such objects. The excess luminosities of the secondary components of all young PVs are indicative of their faster relaxation rate towards the quiescent state compared to the rates estimated in earlier studies.     

Age of the Chibit Glaciation in Gornyi Altai

Doklady Earth Sciences - New results of Optically-Stimulated Luminescence (OSL) dating that make it possible to clarify the age of the Chibitskii glaciation in the Altai Mountains are reported....     

Analysis of fundamental parameters for V477 Lyr

We analyze the photometric and spectroscopic observations of the young pre-cataclysmic variable (pre-CV) V477 Lyr. The masses of both binary components have been corrected by analyzing their radial velocity curves. We show that agreement between the theoretical and observed light curves of the object is possible for several sets of its physical parameters corresponding to the chosen temperature of the primary component. The final parameters of V477 Lyr have been established by comparing observational data with evolutionary tracks for planetary nebula nuclei. The derived effective temperature of the O subdwarf is higher than that estimated by analyzing the object’s ultraviolet spectra by more than 10000 K. This is in agreement with the analogous results obtained previously for the young pre-CVs V664 Cas and UU Sge. The secondary component of V477 Lyr has been proven to have a more than 25-fold luminosity excess compared to main-sequence stars of similar mass. Comparison of the physical parameters for the cool stars in young pre-CVs indicates that their luminosities do not correlate with the masses of the objects. The observed luminosity excesses in such stars show a close correlation with the post-common-envelope lifetime of the systems and should be investigated within the framework of the theory of their relaxation to the state of main-sequence stars.     

The pollution of groundwater and unsaturated zone rocks by oil products and PAH in urban areas

An approach to assessing the hazard of unsaturated zone rocks as a source of subsoil-water secondary pollution by oil products and PAH is considered based on environmental-geochemical studies of soils and rocks of the unsaturated zone, groundwater, and snow, which were carried out during the rehabilitation of the water environment of Lefortovskii Park (Moscow). The impact of the primary pollution sources is analyzed, and the formation of groundwater and rock pollution by oil products and PAH is considered. To assess the role of the unsaturated zone as a secondary source of pollution of surface and subsurface waters under the conditions of possible elimination of the primary sources, the transport of oil products (benzol and toluene) and PAH (pyrene) in unsaturated zone was simulated using WHI UnSat Suite Plus software package.     

The experience of using the rock magnetic methods for assessing the prospects of magnetic exploration in the territory of archaeological monuments of the Barabinsk forest steppe

The results of studying the magnetic properties of the components of the natural environment of the Barabinsk forest steppe accommodating the archaeological monuments dated to VI century B.C. to II century A.D. are presented. The rock magnetic model is constructed for a two-layer medium composed of modern soil and an underlying blanket substratum deposits (clay loam, sandy loam, sand). It is shown that the magnetism of the humic horizon of the soil depends on the topographic position and soil type, whereas the magnetic characteristics of the underlying substratum deposits are persistent throughout the studied territory. The ratio of the magnetic susceptibilities of the humus horizon to the substratum is K = 3–6 for the automorphic soil, K = 1–2.5 for semihydromorphic soil, and K = 0.8–1.0 for hydromorphic soil. Based on subdividing the studied territory in accordance with the values of K and the calculated amplitudes of the microanomalies of the magnetic field, the areas where application of the magnetic survey is highly promising, moderately efficient, and unpromising are outlined. The particular cases of the absence of magnetic anomalies above the archaeological objects, the false anomalies, and the chaotic patterns of the low-amplitude anomalies—all the situations when the magnetic survey is inefficient—are explained from the standpoint of the model.     

230Th/U Dating of Travertines Related to Paleoearthquakes in Gorny Altai: First Results

Doklady Earth Sciences - First 230Th/U-dating results have been obtained for six Quaternary travertine deposits from the southeastern Gorny Altai associated with zones of active faults that bound...