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1.
The domal structures of the Erzgebirge in Saxony, Germany, which control localization of the Variscan hydrothermal U, Sn,
W, and base-metal deposits, started to form in the Late Riphean in the course of folding, regional metamorphism, and granitization
and were eventually created at the end of the Paleozoic, when an enormous mass of granitic melts was emplaced and cooled.
As is illustrated by the world’s largest Schlema-Alberoda vein uranium deposit, the fractures that determined the localization
of ore-bearing veins were formed in the outer contact zones of the Variscan granites related to domal uplifts. Beyond the
zones of contact metamorphism, the orientation of ore-bearing fractures changes, their morphology simplifies, the amplitude
of displacements decreases, and most fractures pinch out. Such a zoning is explained by development of faults around growing
granitic domes. 相似文献
2.
I.?Yu.?Vlasov O.?S.?Sazhina V.?N.?Sementsov M.?V.?SazhinEmail author 《Astronomy Reports》2015,59(6):525-541
Binary stars are considered as possible sources of monochromatic gravitational waves. The amplitude of corrections to the metric generated by such sources is discussed. Three systems that have amplitudes for stresses of the metric exceeding 10?20 are identified (V1182 Aql, V3903 Sgr, and DH Cep). 相似文献
3.
The paths of the movements of hydrothermal solutions are considered in the case of one of the world’s largest uranium vein deposits, the Schlema-Alberoda, which was mined by the Soviet-German corporation Wismut JSC in the second half of the 20th century. Detailed geological exploration to a depth of 2 km was accompanied by specialized research, the results of which have remained practically unpublished due to confidentiality. The data obtained show that the region adjoining the largest fault was draining rather than ore-conducting. This circumstance specifies and supplements the current concept concerning the movement of hydrothermal fluids. 相似文献
4.
The article presents the results of the development of a directional microstrip antenna array with small mass-dimensional characteristics as a directional antenna of the transmitting channel of a small spacecraft. 相似文献
5.
Planetary waves in coupling the lower and upper atmosphere 总被引：1，自引：1，他引：1
A.I. Pogoreltsev A.A. Vlasov K. Frhlich Ch. Jacobi 《Journal of Atmospheric and Solar》2007,69(17-18):2083
The purpose of the paper is to answer the question if planetary waves (PW) are capable of propagating into the thermosphere. First the simplest vertical structure equation of the classic tidal theory accounting for a realistic vertical temperature profile is considered. Analysis and simulation show that the well-known normal atmospheric modes (NM), which are trapped in the lower and middle atmosphere, exhibit a wave-like vertical structure with a large vertical wavelength in the thermosphere. Moreover, the reflection of these modes from the vertical temperature gradient in the lower thermosphere causes appearance of the wave-energy upward flux in the middle atmosphere, and in a linearized formulation this flux is constant above the source region. To investigate a possibility of the NM forcing by stratospheric vacillations and to consider the propagation of different PW up to the heights of the upper thermosphere, a set of runs with a mechanistic Middle and Upper Atmosphere Model has been performed. The results of the simulation show that quasi-stationary and longer-period PW are not able to penetrate into the thermosphere. The shorter-period NM and ultra-fast Kelvin wave propagate up to the heights of the lower thermosphere. However, above about 150 km they are strongly suppressed by dissipative processes. The role of the secondary waves (nonmigrating tides) arising from nonlinear interaction between the primary migrating tides and quasi-stationary PW is discussed. We conclude that PW are not capable of propagating directly up to the heights of the ionospheric F2 region. It is suggested that other physical processes (for instance, the electrostatic field perturbations) have to be taken into account to explain the observed PW-like structures in ionospheric parameters. 相似文献
6.
V. I. Korenbaum S. V. Gorovoy A. A. Tagiltsev A. E. Kostiv A. E. Borodin I. A. Pochekutova A. M. Vasilistov A. C. Krupenkov A. D. Shiryaev D. I. Vlasov 《Doklady Earth Sciences》2016,466(2):187-190
The problem of controlling the state and location of scuba divers is of importance. This work consider the possibility to use for this purpose a low-frequency noise of a scuba diver. The noise of a scuba diver under a dry swimming suite near the trachea and in the water at a distance of 50 m was recorded.It wa shown that both sygnals are characterized by the presence of quasi-periodic components induced by the amplitude modulation of wide-band breathing noises by the brething rhythms of a scuba diver. The quasi-periodic componentss distinguished can be used to evaluate the physiological parameters of the state of a scuba diver and to establish his location. 相似文献
7.
E. V. Glushkova S. E. Koposov I. Yu. Zolotukhin Yu. V. Beletsky A. D. Vlasov S. I. Leonova 《Astronomy Letters》2010,36(2):75-85
Automated search for star clusters in J, H, K
s
data from 2MASS catalog has been performed using the method developed by Koposov et al. (2008). We have found and verified
153 new clusters in the interval of the galactic latitude −24° < b < 24°. Color excesses E(B − V), distance moduli and ages were determined for 130 new and 14 yet-unstudied known clusters. In this paper, we publish a catalog
of coordinates, diameters, and main parameters of all the clusters under study. A special web-site available at has been developed to facilitate dissemination and scientific usage of the results. 相似文献
8.
The commissioning of the RadioAstron space radio telescope observing in a radio-interferometer mode with baselines exceeding the baselines of ground-based VLBI systems by more than an order of magnitude requires revision of the formula used to calculate the delay of the arrival of the signal from a distant source to the telescopes in ground-based observations. This formula is derived taking into account all corrections necessary to achieve the required accuracy; numerical estimates of the contributions of all terms are presented. 相似文献
9.
A. N. Pertsev N. S. Bortnikov E. A. Vlasov V. E. Beltenev I. G. Dobretsova O. A. Ageeva 《Geology of Ore Deposits》2012,54(5):334-346
The oceanic core complexes and large-offset detachment faults characteristic of the slow-spreading Mid-Atlantic Ridge are crucial for the structural control of large hydrothermal systems, including those forming sub-seafloor polymetallic sulfide mineralization. The structural-geological, petrographic, and mineralogical data are considered for the oceanic core complex enclosing the Semenov-1, -2, -3, -4, and -5 inactive hydrothermal sulfide fields recently discovered on the Mid-Oceanic Ridge at 13°31?? N. The oceanic core complex is composed of serpentinized and talc-replaced peridotites and sporadic gabbroic rocks, however, all hydrothermal fields reveal compositional indications of basaltic substrate. The volcanic structures superposed on the oceanic core complex are marked by outcrops of pillow lavas with fresh quenched glass. Dolerites regarded as volcanic conduits seem to represent separate dike swarms. The superposed volcanic structures develop largely along the near-latitudinal high-angle tectonic zone controlling the Semenov-1, -2, -5, and -3 hydrothermal sulfide fields. The manifestations of hydrothermal metasomatic alteration are diverse. The widespread talcose rocks with pyrrhotite-pyrite mineralization after serpentinite, as well as finding of talc-chlorite metabasalt are interpreted as products of hydrothermal activity in the permeable zone of detachment fault. Chloritization and brecciation of basalts with superposed quartz or opal, barite, and pyrite or chalcopyrite mineralization directly related to the sub-seafloor sulfide deposition. The native copper mineralization in almost unaltered basalts at the Semenov-4 field is suggested to precipitate from ore-forming fluids before they reach the level of sub-seafloor sulfide deposition. Amphibolites with plagiogranite veinlets are interpreted as tectonic fragments of the highest-temperature portions of hydrothermal systems, where partial melting of basic rocks in the presence of aqueous fluid with formation of plagiogranitic melt is possible. Silicic rocks (plagiogranite, tonalite and diorite) revealed in the tectonic zone controlling the Semenov-1, -2, -5, and -3 hydrothermal sulfide fields are related to both plutonic and subvolcanic bodies and considered to be products of partial melting of basic rocks at deep levels of the hydrothermal systems. The hydrothermal fields differ in their structural position. The giant Semenov-4 field is located at the area where the hanging-wall basalt wedges out and the detachment fault zone reaches the oceanic floor. The range of relatively small Semenov-1, -2, -3, and 5 fields develops on the oceanic core complex massif, being localized in the superposed volcanic structures within the near-latitudinal steeply dipping tectonic zone. The structural control of the hydrothermal fields at 13°31?? N is also interpreted in different ways. For the Semenov-4 field, the ascending fluid flow can be related to the permeable detachment fault zone. The root zone of the hydrothermal system with a magmatic heater could have been localized at a significant distance beneath the axial spreading zone. For the other four relatively small fields, it is suggested that the ascending fluid flows and roots of the hydrothermal systems are controlled by the volcanic structures superposed on the oceanic ore complex within the steeply dipping tectonic zone. 相似文献
10.
Dzhamalov R. G. Reshetnyak O. S. Safronova T. I. Myagkova K. G. Vlasov K. G. 《Water Resources》2018,45(2):35-43
Water Resources - The present-day conditions of the formation and distribution of the water resources and chemistry under global warming during the recent decades have been considered. The... 相似文献