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61.
A.?V.?StarovoitovEmail author M.?Yu.?Tokarev Ya.?E.?Terekhina N.?A.?Kozupitsa 《Moscow University Geology Bulletin》2018,73(3):295-305
The geological structure of water areas adjacent to the White Sea biological research station of Moscow State University (Rugozero Bay and Great Salma Strait; both are parts of the Kandalaksha Gulf, White Sea) was studied for the first time based on the seismoacoustic data. The morphology of the top of the Achaean basement, the structure of the Quaternary sedimentary cover, and the bottom topography were investigated. The sequence of glacial deposits dated back to the last glaciation and the compound sequence consisting of glaciolacustrine, glacial-marine, and marine sediments are distinguished. The spatial locations and changes of their thicknesses are considered. It is shown that the recent bottom topography is controlled by predominantly NW- and NE-striking faults that run through the entire sedimentary sequence, including the Holocene sediments. 相似文献
62.
E.?S.?SidkinaEmail author I.?A.?Bugaev A.?Yu.?Bychkov A.?G.?Kalmykov 《Moscow University Geology Bulletin》2018,73(4):375-379
Thermodynamic modeling of the hydrothermal exposure of the rocks of the Bazhenov Formation resulted in revealing the equilibrium mineral associations at 50–350°C and the pressure of saturated water vapor. The calculation results show that mineral parageneses varied slightly with the increase of temperature. Thus, zeolites were characterized by the stilbite–laumontite–wairakite series; kaolinite, pyrite, dolomite, and brannerite were replaced by montmorillonite and/or albite, pyrrhotite, calcite, and uraninite, respectively. The modeling results were confirmed in experiments. 相似文献
63.
T.?A.?KhusidEmail author N.?S.?Os’kina N.?P.?Lukashina I.?F.?Gablina N.?V.?Libina A.?G.?Matul 《Stratigraphy and Geological Correlation》2018,26(1):109-120
Comparison of benthic foraminiferal assemblages from the core obtained within the Peterburgskoe ore field (Mid-Atlantic Ridge) and from the core taken five kilometers away from the ore field revealed evident differences in their composition, in the appearance of their shells, and also in the benthic–plankton species ratio. It was noted that the foraminiferal assemblage from the ore-bearing sediments of the Petersburg field was characterized by a higher relative content of benthic species and a large number of chemically altered and broken shells. The first occurrence of the species Osangularia umbonifera, which is able to exist in lowoxygen and CaCO3-undersaturated bottom waters at the boundary of biogenic sediments surrounding the ore field and in the ore-bearing sediments, was established. In the core section sampled beyond the ore field, the composition of foraminiferal assemblages differs insignificantly from typical oceanic ones. 相似文献
64.
Arzu Çöltekin Rebecca Francelet Kai-Florian Richter John Thoresen Sara Irina Fabrikant 《制图学和地理信息科学》2018,45(4):339-353
We report on how visual realism might influence map-based route learning performance in a controlled laboratory experiment with 104 male participants in a competitive context. Using animations of a dot moving through routes of interest, we find that participants recall the routes more accurately with abstract road maps than with more realistic satellite maps. We also find that, irrespective of visual realism, participants with higher spatial abilities (high-spatial participants) are more accurate in memorizing map-based routes than participants with lower spatial abilities (low-spatial participants). On the other hand, added visual realism limits high-spatial participants in their route recall speed, while it seems not to influence the recall speed of low-spatial participants. Competition affects participants’ overall confidence positively, but does not affect their route recall performance neither in terms of accuracy nor speed. With this study, we provide further empirical evidence demonstrating that it is important to choose the appropriate map type considering task characteristics and spatial abilities. While satellite maps might be perceived as more fun to use, or visually more attractive than road maps, they also require more cognitive resources for many map-based tasks, which is true even for high-spatial users. 相似文献
65.
G. A. Richter P. Notni F. Brngen V. Afanasjev I. D. Karachentsev A. Kopylov 《Astronomische Nachrichten》1981,302(5):211-218
With the aid of silt spectrograms gained at the 6 meter telescope Selenchukskaja and at the 2 meter telescope Tautenburg a brightness outburst (the only one so far observed) could be followed up spectroscopically. The spectral behaviour resembles SS Cygni, but the presence of CIII and NIII emission is not typical of dwarf novae. Possibly the object is related to the anomalous recurrent nova WZ Sge. The definite determination of its belonging to a known subclass of cataclysmic variables will be possible only after obtainment of extensive photometric material. 相似文献
66.
G. A. Richter 《Astronomische Nachrichten》1979,300(3):117-119
52 possible optical identifications (V ≲ 19.5) of 43 radio sources of the 5C3 area have been spectroscopically examined by use of objective prism plates from KARL SCHWARZSCHILD Observatory Tautenburg. The aim was to select objects of special interest for further slit spectrographic investigation. Besides 42 probably ordinary stars and 3 galaxies, five quasar spectra have been found, but only one redshift could be determined. Two further objects probably have unusual spectra. 相似文献
67.
A.?Maestro-GonzálezEmail author P.?Bárcenas J.?T.?Vázquez V.?Díaz-del-Río 《Geo-Marine Letters》2008,28(1):53-64
Fractures associated with volcanic rock outcrops on the inner shelf of Alboran Island, Western Mediterranean, were mapped
on the basis of a side-scan sonar mosaic. Absolute maximum fracture orientation frequency is NW–SE to NNW–SSE, with several
sub-maxima oriented NNE–SSW, NE–SW and ENE–WSW. The origin of the main fracture systems in Neogene and Quaternary rocks of
the Alboran Basin (south Spain) appears to be controlled by older structures, namely NE–SW and WNW–ESE to NW–SE faults which
cross-cut the basement. These faults, pre-Tortonian in origin, have been reactivated since the early Neogene in the form of
strike-slip and extensional movements linked to the recent stress field in this area. Fracture analysis of volcanic outcrops
on the inner continental shelf of Alboran Island suggests that the shelf has been deformed into a narrow shear zone limited
by two NE–SW-trending, sub-parallel high-angle faults, the main orientation and density of which have been influenced by previous
WNW–ESE to NW–SE basement fractures. 相似文献
68.
F. Brngen V. E. Karachentseva R. Schmidt G. M. Richter W. Thnert 《Astronomische Nachrichten》1982,303(5):287-292
We present a list of 39 dwarf galaxies of the M 81/82 group. Three different methods are applied to determine their apparent integral magnitude: digital processing, equidensitometry, and calculation according to the formulae of FISHER and TULLY . The plates used were obtained with the Tautenburg Schmidt telescope. For a distance of the group of 3.5 Mpc the absolute magnitudes of the dwarf galaxies investigated are -15m < M < -9m. 相似文献
69.
Altimeter data and output from the HYbrid Coordinate Ocean Model global assimilation run are used to study the seasonal variation
of eddy shedding from the Kuroshio intrusion in the Luzon Strait. The results suggest that most eddy shedding events occur
from December through March, and no eddy shedding event occurs in June, September, or October. About a month before eddy shedding,
the Kuroshio intrusion extends into the South China Sea and a closed anticyclonic eddy appears inside the Kuroshio loop which
then detaches from the Kuroshio intrusion. Anticyclonic eddies detached from December through February move westward at a
speed of about 0.1 m s−1 after shedding, whereas eddies detached in other months either stay at the place of origin or move westward at a very slow
speed (less than 0.06 m s−1). The HYCOM outputs and QuikSCAT wind data clearly show that the seasonal variation of eddy shedding is influenced by the
monsoon winds. A comparison between eddy volume and integrated Ekman transport indicates that, once the integrated Ekman transport
exceeds 2 × 1012 m3 (which roughly corresponds to the volume of an eddy), the Kuroshio intrusion expands and an eddy shedding event occurs within
1 month. We infer that the Ekman drift of the northeasterly monsoon pushes the Kuroshio intrusion into the SCS, creates a
net westward transport into the Strait, and leads to an eddy detachment from the Kuroshio. 相似文献
70.
M. Capaccioli E. V. Held H. Lorenz G. M. Richter R. Ziener 《Astronomische Nachrichten》1988,309(2):69-80
This study reports on the results of the application of an adaptive filtering technique to the two-dimensional photometric mapping of galaxies. For this test we used the elliptical galaxy NGC 3379, which is a luminosity standard. Our plate material (B-band), obtained with the Tautenburg Schmidt telescope, was digitized with the Babelsberg microdensitometer and with the ESO PDS. The 2-D scans were reduced according to the Babelsberg Image Processing Systems, whose key feature is an adaptive filter called ‘H-Transform’. By comparing our results (E-W light profile and isophotal parameters) to the most recent studies of NGC 3379 (DE VAUCOULEURS and CAPACCIOLI 1979, and NIETO and VIDAL 1984), we found no systematic errors in the photometric calibration and in the reduction procedure, with typical mean residuals from the other studies not larger than ±0.05 B-mag up to a threshold of 1% of the night sky level on each plate. We also re-confirmed the geometrical properties of the galaxy. The new filtering technique proved quite efficient in reducing the noise, with negligible effects on the photometric and geometric characteristics of the star-like sources. 相似文献