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991.
Doklady Earth Sciences - The interaction between the atmosphere and the lithosphere in the minute range of periods is considered. The technique of assessment of the influence of atmospheric...  相似文献   
992.
The weathering crust of the Beden ultrabasite massif (the basin of Big Laba River) is identified and studied. Anomalously high contents of noble metals (Au, Pt, Pd) are revealed in the basal horizon of the Jurassic part of the weathering crust. For this reason we suspect an existence of a belt of noble metal miner-alization in the Paleozoic ultrabasites in the Peredovoi Range of the Northern Caucasus.  相似文献   
993.
The evolution and collapse of a gaseous, self-gravitating sphere in the presence of an internal massive toroidal vortex analogous to the vortex created by the toroidal magnetic field of the Sun is considered. When thermal pressure is taken into account, for sufficiently high masses, the instability is preserved even for a polytropic index γ < 4/3. In the case of a degenerate gas, the evolution of the electrons and neutrons differs appreciably. In the ultrarelativistic limit, an interval of stablemasses arises in a neutron gas, between a minimum mass that depends on the circulation velocity in the vortex and the critical mass for the formation of a black hole. This suggests toroidal vortex fields as a possible physical origin for the observed narrow spectrum of neutron-star masses.  相似文献   
994.
995.
Geomagnetism and Aeronomy - The arc-polarized Alfvén waves observed in the near-Earth region of the heliosphere are studied with instruments of the WIND spacecraft in 1995–2011....  相似文献   
996.
We solve a plane problem of linear baroclinic seiches in closed rotating basins of variable depth with two-layer density stratification. In the long-wave approximation, we get a boundary-value problem for a system of ordinary differential equations and propose a numerical procedure for finding internal seiches. The analytic solutions of the problem are obtained for a basin of constant depth. The numerical analysis of seiches is performed for the distributions of depth corresponding to the zonal and meridional sections of the Black Sea and model basins including the cases of a shelf zone and an underwater ridge. It is shown that the baroclinic seiches become more intense in shallow-water regions and that the intense longshore currents caused by Earth’s rotation are formed in the shelf zones and over the underwater ridges.  相似文献   
997.
Vul'fson  A. N.  Borodin  O. O. 《Water Resources》2000,27(6):625-632
An intergral model of a transient vertical impulse–buoyant jet is suggested. The model contains a universal equation describing the propagation of the upper boundary of the convection front depending on the strength of the point source of buoyancy and momentum. The convective regime of jet propagation is considered, which includes a class of self-similar solutions corresponding to the buoyancy sources, whose strength varies with time following power and exponential laws. The obtained numerical solutions are compared with available experimental data on the profiles of vertical velocity and buoyancy on the jet axis.  相似文献   
998.
Proposed are the methods and software package that enable estimating automatically the degree of the pollution of annual and long-term river runoff at the joint processing of large volumes of standard (routine) hydrological and hydrochemical information. As a result of computations, the individual quality certificate of river runoff was created for the part of the river under study. Computation methods include regulations concerning the parameters that connect the water runoff volume with water quality; the parameters that may connect the computation of the pollution degree using RD 52.24.643-2002 adapted for the partial volumes of the annual runoff according to these methods, with the subsequent classification of the pollution degree. The computation technique was worked out and used for the first time. The informativeness of estimates is demonstrated for one of the discharge section lines of the Selenga River.  相似文献   
999.
Introduction The eastern margin of the Tibetan Plateau, adjacent to the Sichuan Basin (Figure 1), has become a testing ground for a variety of models that contrast mechanisms of extrusion and crustal thickening associated with the India-Asia collision (Avouac and Tapponnier 1993, England and Houseman 1986),but that also address the extent to which the upper crust and upper mantle are coupled (Royden et al. 1997, Holt 2000). The margin is characterized by topographic relief of over 5 km an…  相似文献   
1000.
Both a theoretical treatment and observed data show that the isostatic gravity field and the seismicity are closely related. The equation for harmonic loading shows that large deviations from isostatic equilibrium lead to large shear stresses in the crust. High seismic activity correlates well with large isostatic gravity anomalies and with large horizontal gradients of isostatic gravity anomalies. Studies of seismicity should consider the isostatic gravity field.  相似文献   
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