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951.
V. B. Zalesny V. I. Agoshkov V. P. Shutyaev F. Le Dimet B. O. Ivchenko 《Izvestiya Atmospheric and Oceanic Physics》2016,52(4):431-442
Models and methods of the numerical modeling of ocean hydrodynamics dating back to the pioneering works of A.S. Sarkisyan are considered, with emphasis on the formulation of problems and algorithms of mathematical modeling and the four-dimensional variational assimilation of observational data. An algorithm is proposed for studying the sensitivity of the optimal solution to observational data errors in a seasurface temperature assimilation problem in order to retrieve heat fluxes on the surface. An example of a solution of the optimal problem of the World Ocean hydrodynamics with the assimilation of climatic temperature and salinity observations is offered. 相似文献
952.
G. K. Korotaev Yu. B. Ratner M. V. Ivanchik A. L. Kholod A. M. Ivanchik 《Izvestiya Atmospheric and Oceanic Physics》2016,52(5):542-549
The automatic system of operational forecasting of the Black Sea state which functions at the Marine Hydrophysical Institute is presented. Principles of the system construction are considered; the marine environment models used for forecasting, the data streams required for the system functioning, and tools for validating and visualizing the results of sea-state calculations are described. Some examples of investigating a number of processes and phenomena in the Black Sea are given. 相似文献
953.
V. G. Bondur V. A. Dulov A. B. Murynin V. Yu. Ignatiev 《Izvestiya Atmospheric and Oceanic Physics》2016,52(6):637-648
A method to register sea-wave spectra using optical aerospace imagery has been developed. The method is based on the use of retrieval operators both in areas of high and low spatial frequencies, including the areas of spectral maximum. The approach to adjust and validate the method developed using sea truth data obtained by string wave recorders has been suggested. This paper presents the results of using the suggested method to study sea-wave spectra using high-resolution satellite imagery for various water areas under different conditions of wave generation. 相似文献
954.
V. M. Savatenkov A. M. Kozlovsky V. V. Yarmolyuk Z. B. Smirnova 《Doklady Earth Sciences》2016,470(1):985-989
Based on study of the Middle Paleozoic (Hercynian) structures of the Central Asian Fold Belt located in Southwest Mongolia, the problem of the sources of juvenile crust growth registered in the Pb isotope composition of postaccretional granitoids is considered. Our study shows that the Pb isotope system of Late Paleozoic granitoids from the Hercynides of the Central Asian Fold Belt provides evidence for the juvenile nature of the continental crust in this region. The evolution of the Pb isotope composition in the Hercynides of Mongolia corresponds to the model parameter μ = 9.25, according to the Stacey–Kramers twostage model. The juvenile source of the Hercynian crust should be characterized by a lower μ value. In addition, according to the Stacey–Kramers two-stage model, the Th/U value in this crust is 3.58. 相似文献
955.
S. F. Vinokurov A. G. Gurbanov O. A. Bogatikov V. A. Sychkova A. V. Shevchenko A. B. Lexin Z. I. Dudarov 《Doklady Earth Sciences》2016,470(2):1034-1036
The decontamination of buried wastes of the Tyrnyauz Tungsten–Molybdenum Plant is complicated by the geochemical features of the waste composition: low sulfide and high carbonate content, polyelemental composition, and considerable amounts of technogenic admixtures (kerosene, oils, soda, and soluble glasses). These circumstances result in sufficient complication of the suggested technology of waste treatment, including the sulfuric-acid leaching and separate sorption recovery of hazardous and useful elements from the working solution. 相似文献
956.
V. B. Lapshin A. V. Patonin A. V. Ponomarev M. G. Potanina V. B. Smirnov S. M. Stroganova 《Doklady Earth Sciences》2016,469(1):705-709
A rock behavior experiment with uniaxial compression revealed the effect of acoustic activity in loaded fluid-saturated Berea sandstone samples in response to an electric current. It is established that it is substantially intensified in periods of the current impact and decreases after its cut-off. The current impact also results in a growth of radial deformation indicating an increase in the sample volume. The effect of acoustic activation increases in response to increased heat emitted by the electric current during its flow through the sample, which allows the discovered effect to be explained by initiation of its destruction due to thermal expansion of the fluid in rock interstices and fissures. 相似文献
957.
A. B. Makeev T. B. Bayanova S. E. Borisovsky O. M. Zhilicheva 《Geology of Ore Deposits》2016,58(8):646-652
This study focuses on the morphological features, color cathodoluminescence, chemical composition, age, and source of zircons from the Ichet’yu occurrence. The isotopic U–Pb age of Paleo–Mezoproterozoic zircon grains varies within an interval of ~700 Ma from 2247 to 1478 Ma. The average roundness and well-preserved integrity of zircon grains allow us to suggest their proximal source. The available data show that the basement of the Middle Timan, composed of continental Paleo–Mezoproterozoic igneous rocks, is the most probable source of zircon in the Ichet’yu occurrence. These rocks are apparently a continuation of the Archean–Proterozoic Arkhangel’sk Mobile Belt. 相似文献
958.
The results of JHKLM photometry of two carbon stars are presented: the irregular variable NQ Cas and the Mira star BD Vul. Data on the mean fluxes supplemented with mid-IR observations with the IRAS, AKARI, andWISE satellites are used to compute spherically symmetrical model dust envelopes for the stars, consisting of particles of amorphous carbon and silicon carbide. The optical depth in the visible for the comparatively cool dust envelope of BD Vul, with a dust temperature at its inner boundary T1 = 610 K, is fairly low: τV = 0.13. The dust envelope of NQ Cas is appreciably hotter (T1 = 1550 K), and has τV = 0.32. The estimated mass-loss rates are 1.5 × 10?7M⊙/yr for NQ Cas and 5.9 × 10?7M⊙/yr for BD Vul. 相似文献
959.
The suitability of geologic frameworks for extrapolating hydraulic conductivity (K) to length scales commensurate with hydraulic data is difficult to assess. A novel method is presented for evaluating assumed relations between K and geologic interpretations for regional-scale groundwater modeling. The approach relies on simultaneous interpretation of multiple aquifer tests using alternative geologic frameworks of variable complexity, where each framework is incorporated as prior information that assumes homogeneous K within each model unit. This approach is tested at Pahute Mesa within the Nevada National Security Site (USA), where observed drawdowns from eight aquifer tests in complex, highly faulted volcanic rocks provide the necessary hydraulic constraints. The investigated volume encompasses 40 mi3 (167 km3) where drawdowns traversed major fault structures and were detected more than 2 mi (3.2 km) from pumping wells. Complexity of the five frameworks assessed ranges from an undifferentiated mass of rock with a single unit to 14 distinct geologic units. Results show that only four geologic units can be justified as hydraulically unique for this location. The approach qualitatively evaluates the consistency of hydraulic property estimates within extents of investigation and effects of geologic frameworks on extrapolation. Distributions of transmissivity are similar within the investigated extents irrespective of the geologic framework. In contrast, the extrapolation of hydraulic properties beyond the volume investigated with interfering aquifer tests is strongly affected by the complexity of a given framework. Testing at Pahute Mesa illustrates how this method can be employed to determine the appropriate level of geologic complexity for large-scale groundwater modeling. 相似文献
960.
Fluid exchange across the sediment–water interface in a sandy open continental shelf setting was studied using heat as a tracer. Summertime tidal oscillation of cross-shelf thermal fronts on the South Atlantic Bight provided a sufficient signal at the sediment–water interface to trace the advective and conductive transport of heat into and out of the seabed, indicating rapid flushing of ocean water through the upper 10–40 cm of the sandy seafloor. A newly developed transport model was applied to the in situ temperature data set to estimate the extent to which heat was transported by advection rather than conduction. Heat transported by shallow 3-D porewater flow processes was accounted for in the model by using a dispersion term, the depth and intensity of which reflected the depth and intensity of shallow flushing. Similar to the results of past studies in shallower and more energetic nearshore settings, transport of heat was greater when higher near-bed velocities and shear stresses occurred over a rippled bed. However, boundary layer processes by themselves were insufficient to promote non-conductive heat transport. Advective heat transport only occurred when both larger boundary layer stresses and thermal instabilities within the porespace were present. The latter process is dependent on shelf-scale heating and cooling of bottom water associated with upwelling events that are not coupled to local-scale boundary layer processes. 相似文献