Tectonics and metallogeny of the Khakandzha ore district in the Okhotsk–Chukotka volcanic belt

The data on the structure, geodynamics, and metallogeny of the Khakandzha ore district in northwestern Okhotsk region are analyzed and the two main factors responsible for the localization of ore deposits are defined. The magmatic factor controls the confinement of the ore district to the tectono-magmatic structure of the central type (source of ore matter), which determines the concentric zoning patterns in the distribution of ore mineralization. The tectonic factor determines the confinement of the ore districts, deposits, and ore occurrences of the region to the meridional left-lateral shear structure, which controls the magma and fluid distribution. Local extension (transtension) in this structure against the background of general lateral compression (transpression) provided tectonic environments most favorable for ore accumulation.     

Hysteresis effect in nutrient sorption by boggy sediments

The role of bogs as filters on the path of pollutant migration to surface and subsoil waters is demonstrated. Sorption hysteresis is shown to play a major role in the retention of pollutants by peat mass. The mathematical problem of pollutant transport and absorption in bogs is formulated and solved numerically.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 205–213.Original Russian Text Copyright © 2005 by Belyaev, Dzhamalov, Krichevets, Polyakova, Yushmanov.     

Changes in the Ecological Condition of a Territory at the Construction of Buildings with a Deep Foundation under Various Geological Conditions in Moscow

Water Resources - Mathematical modeling was used to identify zones with different magnitudes of the barrage effect on the construction of buildings with deep-laid foundation in the Moscow region....     

Principles of MSW Landfill Sites’ Placement Depending on Geological and Hydrogeological Conditions of Territories (Based on Moscow Region)

Water Resources - More than 31 billion tons of unutilized waste have accumulated in Russia, and this amount is increasing every year. The dump sites’ locations require profound scientific...     

Seawater intrusion into coastal aquifers

The hydrological, hydrophysical, and hydrochemical aspects of the interaction between marine waters and groundwater in the adjacent land territory as a manifestation of the general process of interaction between surface and subsurface waters. Most attention is concentrated on the marine water intrusion into aquifers. Recent achievements in the field of modeling seawater intrusion into coastal aquifers are reviewed.     

Assessing the Hazard of Environmental Pollution by Landfills of Industrial and Municipal Wastes

Water Resources - The environmental effect of landfills of solid municipal wastes is considered, including their effect on groundwater. The accumulation of municipal wastes causes considerable...     

Modeling Salt-Accumulation Processes in Subsoil Waters in Areas with Insufficient Moistening

Equations of flow in water-saturated porous medium and advection diffusion of dissolved salts are used to study salt transport and accumulation in subsoil water. One-dimensional and two-dimensional models of joint movement of subsoil water and dissolved salts are proposed based on the generalized law of liquid flow in porous medium with the density depending on the concentration of dissolved substances. The models allow taking into account various hydrological and hydrophysical factors affecting mass transport.     

Spreading of Acidification Front in Subsoil Water within a Waterlogged Watershed

The effect of atmospheric precipitation on the hydrogeochemical regime of subsoil water is studied in the case of Usad'e watershed in Novgorod oblast. Thermodynamic and mathematical models are used to generalize the results of long-term hydrogeological studies and predict the propagation of acidification front in groundwater flow.     

Assessment of groundwater inflow in urban territories

Analytical and numerical methods are proposed for the calculation of water inflow into construction pits under various geological—engineering and hydrogeological conditions at the construction site. Water inflow into the pit is shown to depend not only on lateral seepage but also on the leakage from underlying aquifers at appropriate parameters of their interaction. Under certain natural conditions, the most efficient method for construction pit draining at low water yield of soils in the construction area are light wellpoint systems, the capacity and layout of which is determined by the potential inflow through the pit contour. The results of analytical and numerical calculations for the assessment of groundwater inflow into a pit are given, and light wellpoint systems are shown to be effective under different combinations of natural and engineering conditions.