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61.
Nazarova D. P. Portnyagin M. V. Krasheninnikov S. P. Mironov N. L. Sobolev A. V. 《Doklady Earth Sciences》2017,472(1):100-103
Doklady Earth Sciences - The formation conditions of the parental magmas of Gorely volcano, which is located behind a volcanic front in Southern Kamchatka, have been evaluated using the modern... 相似文献
62.
M.I. Epov V.L. Mironov K.V. Muzalevskiy I.N. Eltsov U.P. Salomatov 《Russian Geology and Geophysics》2013,54(9):1103-1107
A theoretical study has been performed to check the possibility of using ultrabroadband nanosecond electromagnetic pulses as a geosteering tool for horizontal drilling to estimate the distance to the oil-water contact (OWC) in a floating oil accumulation. The voltage of a microwave-bandwidth pulse at the dipole receiver of a downhole radar was modeled for the case of a horizontal borehole near OWC in a formation saturated with oil and water. Numerical solutions to the boundary problem formulated on the basis of the Maxwell equations were obtained with the Microwave Studio software (www.cst.com). The frequency-dependent dielectric constants of the layered saturated formation and the drilling fluid were assumed according to experimentally tested models. The modeling has demonstrated that nanosecond electromagnetic pulses arriving from a layered oil-water contact can in principle be acquired and the distance from the wellbore to the OWC median can be inferred from the respective time delays recorded by a downhole radar. Additionally, the possible dynamic range and accuracy of sensing have been estimated. 相似文献
63.
The Pogranichnoe ore occurrence of gold-bismuth type is closely related to Ordovician granitic rocks pertaining to the Sarkhoi granodiorite-granite complex of calc-alkaline series. This type of mineralization in the Eastern Sayan is described for the first time. The orebodies are represented by quartz veins and veinlets with greisenized granite as selvages. Three mineral assemblages consecutively follow one another: (1) pyrite-arsenopyrite, (2) base-metal with fahlore and Sb sulfosalts, and (3) gold-bismuth. The geological position of orebodies and character of microinclusions in accessory minerals of granites suggest that goldbismuth mineralization is related to granitoids. 相似文献
64.
On the basis of detailed fieldwork and analytical procedures (microprobe, X-ray diffraction, chemical analysis, etc.), ores
and altered wall-rock rocks of the Khadatkanda and Etyrko deposits in the Kodar-Udokan mineragenic zone were studied. Economic
concentrations of gold and some other accompanying metals have been established in ore of the Khadatkanda uranium deposit
in the Syul’ban uranium district. REE-U lodes with brannerite-uraninite have been found at the Etyrko Fe-Ti-V deposit related
to the Chinei layered pluton in the Udokan mining district. The outlook for the discovery of new types of economic uranium
deposits is substantiated with respect to the known hydrothermal uranium ore objects and nontraditional setting related to
the layered mafic-ultramafic intrusions. 相似文献
65.
Milyukov V. K. Amoruso A. Crescentini L. Mironov A. P. Myasnikov A. V. Lagutkina A. V. 《Izvestiya Physics of the Solid Earth》2019,55(3):389-396
Izvestiya, Physics of the Solid Earth - The free core nutation (FCN) is one of the Earth’s rotational eigenmodes, which is caused by the retrograde motion of the liquid core relative to the... 相似文献
66.
V. K. Milyukov A. Amoruso L. Crescentini A. P. Mironov A. V. Myasnikov A. V. Lagutkina 《Izvestiya Physics of the Solid Earth》2018,54(2):336-348
Reliable use of strain data in geophysical studies requires their preliminary correction for ocean loading and various local distortions. These effects, in turn, can be estimated from the tidal records which are contributed by solid and oceanic loading. In this work, we estimate the oceanic tidal loading at two European strain stations (Baksan, Russia, and Gran Sasso, Italy) by analyzing the results obtained with the different Earth and ocean models. The influence of local distortions on the strain measurements at the two stations is estimated. 相似文献
67.
V. K. Milyukov A. P. Mironov G. M. Steblov A. N. Ovsyuchenko E. A. Rogozhin V. N. Drobyshev A. G. Kusraev Kh. M. Khubaev Kh. -M. Z. Torchinov 《Izvestiya Physics of the Solid Earth》2017,53(4):598-605
A geodetic network of Global Satellite Navigation System (GNSS) observation sites was organized in 2014–2015 for studying the contemporary crustal motions in the zone of the Vladikavkaz deep fault (Milyukov et al., 2014; 2015). The measurements were conducted and the first velocity estimates obtained testifying to the consistency of crustal motions in the Vladikavkaz fault zone and the Ossetian region overall in the ITRG2008 system. The first results show that the velocities and directions of horizontal motions do not change upon the transition of the fault zone. In correspondence with the northeastern orientation of the site displacement vectors and sublatitudinal trend of the disjunctive zone, the presence of left-lateral strike-slip displacements along the branches of an active fault should be expected. However, the signs pointing to the activation of motion in the fault zone are absent. Besides, even the manifestation of weak seismicity has not been observed within the high-magnitude seismogenic Vladikavkaz zone associated with this fault for more than 25 years. This suggests the passive present state of this structure, one of the largest disjunctive structures of the Northern Caucasus. In order to verify this conclusion and revealing the kinematic pattern of the displacements associated with the fault structure it is reasonable to continue the measurements. 相似文献
68.
M.?A.?Magus’kinEmail author I.?K.?Mironov K.?M.?Magus’kin 《Journal of Volcanology and Seismology》2017,11(3):206-216
This paper presents all direct precise leveling measurements of elevations between permanent benchmarks that stand along two lines in the Avacha Geodynamic Test Site from 1962 to 1995. These data are of special importance for future researchers. We show that the vertical strain increases as one approaches the volcanic edifice, while at the same time being oscillatory in character. The fluctuations of benchmark elevations at distances of 6–7 km from the volcano show amplitudes of –4.2 cm to +3.0 cm relative to a benchmark that is 17.4 km distant from the crater. It is hypothesized that the oscillatory character of vertical movements around the volcano is due to the varying influence of crustal stresses on the magma chamber beneath the volcano and these stresses are subject to variation in the subduction zone of the Pacific and Eurasian plates. Under these conditions the magma chamber “operates” as a natural giant strainmeter. The leveling observations revealed subsidence on the shore of Avacha Bay in the seaport area, probably by as much as over 13 cm at the time of the large earthquake that occurred in November 1971 and whose epicenter was in the Avacha Bay at a distance of approximately 70 km from the city. 相似文献