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991.
New data on the mineral composition of the Ozernoye meteorite, found in the Kurgan region in 1983, are presented. It has been found that that the meteorite’s matter is composed of olivine (chrysolite), orthopyroxene (bronzite), clinopyroxene (augite), maskelynite, chromite, ilmenite, metals Fe and Ni (kamasite, taenite), sulfides (troilite, pentlandite), chlorapatite, and merrillite. Augite, taenite, pentlandite, and merrillite were identified in the Ozernoye meteorite for the first time. The chemical compositions are given for all these minerals. The meteorite itself is an ordinary chondrite stone belonging to petrological type L5.  相似文献   
992.
The magnetic-field structure in regions of stationary, planar accretion disks around active galactic nuclei where general-relativistic effects can be neglected (from 10 to 200 gravitational radii) is considered. It is assumed that the magnetic field in the outer edges of the disk, which forms in the magnetosphere of the central black hole during the creation of the relativisitic jets, corresponds to the field of a magnetic dipole perpendicular to the plane of the disk. In this case, the azimuthal field component Bφ in the disk arises due to the presence of the radial field Bρ and the azimuthal velocity component Uφ. The value of the magnetic field at the inner radius of the disk is taken to correspond to the solution of the induction equation in a diffusion approximation. Numerical solutions of the induction equation are given for a number of cases.  相似文献   
993.
The results of study of the deep sources of volcanic rocks from the Sea of Japan and the Philippine Sea with continental and oceanic basements, respectively, are presented. This problem is considered with the example of alkaline volcanic rocks of the Middle Miocene to Pliocene complex of the Sea of Japan and the Eocene–Oligocene Urdaneta Plateau of the Philippine Sea. The rocks have a similar geochemistry typical of OIBs, which indicates their deep (plume) origin. The presence of the Oligocene calc-alkaline volcanic rocks, which were formed prior to the marginal sea volcanism in the Sea of Japan, however, is the main difference in volcanism of the Sea of Japan from that of the Urdaneta Plateau, and this is explained by the different basements of these seas.  相似文献   
994.
In-situ monitoring observations are carried out, and correlation analysis aimed at estimating the dependences between the electromagnetic parameters (variations of apparent resistivity, the impedance phase, components of the impedance tensor, and deformations of the daylight surface on the territory of the Bishkek geodynamic polygon) is performed. A new approach to the explanation of the physical mechanism forming variations in electrical conductivity of the medium is proposed on this basis.  相似文献   
995.
Basic chemical and mineralogical anomalies in permafrost caused by hydrocarbon migration are considered. Direct evidence for bacterial oxidation of light hydrocarbons, primarily methane, were first obtained in fluid permeability zones in the permafrost as a stepwise formation of authigenic minerals such as iron sulfides and oxides, carbonates, silicates, and gypsum.  相似文献   
996.
The dependence of the emission measure on the dispersion measure due to the Galactic background has been derived for 120 directions in the Galaxy. This analysis has yielded the mean electron density, effective thickness of the electron layer, and the volume filling factor of the clouds of ionized gas along the line of sight. The pulsar J1745?2900, which lies in a direction close to the direction toward the center of the Galaxy, is located at least 100 pc closer to the observer than the source Sgr A* along the line of sight. The scatter-broadened angular size of J1745?2900 is determined by the turbulent medium in the Sagittarius Arm.  相似文献   
997.
The results of spectral observations of the region of massive star formation L379IRS1 (IRAS18265–1517) are presented. The observations were carried out with the 30-m Pico Veleta radio telescope (Spain) at seven frequencies in the 1-mm, 2-mm, and 3-mm wavelength bands. Lines of 24 molecules were detected, from simple diatomic or triatomic species to complex eight- or nine-atom compounds such as CH3OCHO or CH3OCH3. Rotation diagrams constructed from methanol andmethyl cyanide lines were used to determine the temperature of the quiescent gas in this region, which is about 40–50 K. In addition to this warm gas, there is a hot component that is revealed through high-energy lines of methanol and methyl cyanide, molecular lines arising in hot regions, and the presence of H2O masers and Class II methanol masers at 6.7 GHz, which are also related to hot gas. One of the hot regions is probably a compact hot core, which is located near the southern submillimeter peak and is related to a group of methanol masers at 6.7 GHz. High-excitation lines at other positions may be associated with other hot cores or hot post-shock gas in the lobes of bipolar outflows. The rotation diagrams can be use to determine the column densities and abundances of methanol (10?9) and methyl cyanide (about 10?11) in the quiescent gas. The column densities of A- and E-methanol in L379IRS1 are essentually the same. The column densities of other observedmolecules were calculated assuming that the ratios of the molecular level abundances correspond to a temperature of 40 K. The molecular composition of the quiescent gas is close to that in another region of massive star formation, DR21(OH). The only appreciable difference is that the column density of SO2 in L379IRS1 is at least a factor of 20 lower than the value in DR21(OH). The SO2/CS and SO2/OCS abundance ratios, which can be used as chemical clocks, are lower in L379IRS1 than in DR21(OH), suggesting that L379IRS1 is probably younger than DR21(OH).  相似文献   
998.
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   
999.
Syn-ore centroid type deformations that produced unusual structural assemblages are identified in the Uryakh ore field. The regularities of the deformation process comparable to a mechanism of the centroid-type seismic focus are established. The results of studying fluid inclusions suggest that the pressure—temperature parameters of the system correspond to conditions typical of the seismic regime. A model of formation of structural assemblages in a centroid-type dynamic regime with the participation of fluids is proposed for the first time.  相似文献   
1000.
The first data on abnormally high δ13С values in hydrocarbonates (НСО 3-) dissolved in underground waters of coal deposits of Kuzbass (up to +30.9‰) are reported. It is shown that such an unusual isotope composition of waters results from the long, strictly directed interaction in the water–rock–gas–organic material system occurring under the conditions of hindered water exchange. Extensive fractionation of C isotopes is the result of the evolution of the water–rock–gas–coal system after penetration of infiltration waters into the coal deposits and their long interaction with all these components, rather than metamorphism of organic material upon its transformation into coal. With respect to such an approach, the isotope composition of dissolved C may indicate the duration of the evolution in the water–rock–gas–organic material system.  相似文献   
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