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291.
Prof. Dr. A. Watznauer 《International Journal of Earth Sciences》1965,54(2):853-860
Zusammenfassung Es läßt sich zeigen, daß im erzgebirgischen Raum die jungalgonkische Serie des varistischen Sockels von der Petrofazies diskordant geschnitten wird. Im Bereich des erzgebirgischen Kristallins steigt die Amphibolitfazies beulenförmig bis an die Basis des varistischen Sedimenttroges auf. Mit diesem Aufstieg wird eine Granitbildung regionalen und lokalen Charakters als möglich in Verbindung gebracht.
Herrn Prof. Dr. Dr. h. c.Erich Bederke zum 70. Geburtstag gewidmet. 相似文献
It can be demonstrated that the Upper Algonkian rocks of the Hercynian basement are disconformably cut by the petrofacies of the Erzgebirge. In the environment of crystallin rocks amphibolitic facies ascend to the bottom of the hercynian sedimentary trough. With this rise a granitisation of regional and locally restricted character might seem to be possible.
Résumé On peut montrer que dans la région de l'Erzgebirge les couches de l'Algonkien supérieur du socle hercynien sont recoupées en discordance par le petrofacies. Dans le domaine du cristallin de l'Erzgebirge, le facies amphibolite a la forme d'un dûme atteignant la base de la fosse sédimentaire varisque. On croit pouvoir établir une relation entre la formation de granite à l'échelle régionale et locale et cette montée métamorphique.
. .
Herrn Prof. Dr. Dr. h. c.Erich Bederke zum 70. Geburtstag gewidmet. 相似文献
292.
Relationships among conductivity, temperature, total dissolved solids (TDS), and density were determined for hypersaline brine
(TDS, 83 g kg−1) from Mono Lake. A theoretical estimate of density based on ionic composition and calculated partial molar volumes compared
well with actual measurements (difference, 390 ppm). However, an empirically derived equation of state based on temperature
and conductivity provides the most accurate density estimates (residual errors, 190 ppm) and can be used with data collected
with CTD profilers. 相似文献
293.
294.
295.
Summary This paper concerns the use of airborne or ground-based Doppler radars to observe precipitating systems over complex orography.
As nearly all of the previous experiments involving Doppler radars were conducted over flat surfaces over the continents or
the oceans, new techniques are needed firstly to separate ground clutter from meteorological signal and, in the case of airborne
Doppler observations, to deduce navigational errors. Secondly, it is necessary to take the atmospheric circulation induced
by orography into account in the three-dimensional wind field analysis. Variational techniques are presented to solve these
problems.
The proposed methods are tested with simulated ground-based and airborne Doppler radar observations for analytic flows over
analytic terrains and for numerically simulated wind and reflectivity fields for the Brig event (22 September 1993) of heavy
precipitation over the southern flank of the Alps (Cosma and Richard, 1998), and with actual airborne Doppler data relative
to weak snow showers over the Rocky Mountains on 12 March 1995.
Received March 22, 1999/Revised June 1, 1999 相似文献
296.
The transport of bromide (Br) under matric heads of 0, ?2, ?5, and ?10 cm using undisturbed soil columns was investigated for understanding the solute transport in arid soils. Undisturbed soil cores were collected at ground surface, directly below where tension infiltrometer measurements were made in the Amargosa Desert, Nevada, United States. Laboratory experiments were conducted by introducing water containing Br tracer into a soil column maintained at steady‐state conditions. The observed data of breakthrough curves (BTC) were well fitted to an one‐region model, except for the cores at saturation, and a core at the matric head of ?5 cm, from which the observed data were better fitted to a two‐region model. Fitted pore water velocities with the one‐region model ranged from 1.2 to 56.6 cm/h, and fitted dispersion coefficients (D) ranged from 2.2 to 100 cm2/h. Results for the core analyzed with the two‐region model indicated that D ranged from 27.6 to 70.9 cm2/h at saturation, and 25.7 cm2/h at the matric head of ?5 cm; fraction of mobile water (β) ranged from 0.18 to 0.65, and mass transfer coefficient (ω) ranged from 0.006 to 0.03. In summary, the water fluxes and Br dispersion coefficients at investigated matric heads were very high due to the coarseness of the soils and possibly due to preferential flow pathways. These high water fluxes and Br dispersion coefficients would lead to a higher risk of deeper leaching accumulating nitrate nitrogen to the groundwater, and have significant effects on the desert ecosystem. 相似文献
297.
298.
This paper investigates the impact of a 1000‐year flood in August 2002 on floodplains and valley morphology of an Austrian mixed alluvial bed rock river. Discharges with a recurrence interval between 500 and 2000 years caused distinctive overbank scouring and material deposition in the floodplains. After the 1000‐year flood, those morphologically affected areas were at random intervals documented over the whole longitudinal profile. In addition to overbank erosion in curved sections (cut‐offs), the river bed locally widened, floodplain stripping occurred and local overbank scours were documented along straight parts of the river. A hydrodynamic‐numerical model, combined with field measurements, was used to analyse the cause of these erosional landforms. Based on the modelled hydraulic conditions for a one‐year flood (30–78 m3 s–1) and the catastrophic 2002 event (700–800 m3 s–1), the numerical results allowed a cause‐effect study with 19 parameters. Deterministic and statistical analysis (ANOVA, discriminant analysis) showed that the morphodynamic effects of the 2002 flood were influenced by the variability of valley morphology of the Kamp River, which led partially to supercritical flow during flood constriction. These processes were in some cases also anthropogenically influenced. Lateral constriction and expansion of the valley geometry over short distances led to scouring and aggradation within the inundated areas during the event. These morphological features were therefore responsible for the elongated scour holes in the floodplains. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
299.
David L. Finnegan Janet P. Kotra Diane M. Hermann William H. Zoller 《Bulletin of Volcanology》1989,51(2):83-87
A simple system was designed using7LiOH-impregnated filters to collect acidic gases from ambient air and from highly concentrated volcanic plumes or gas streams. These filters were developed for analysis using instrumental neutron activation analysis, but other analytical techniques could be used as well. The sampling system was designed to use a series of 1–3 M7LiOH-impregnated filters to collect high concentrations of acidic gases found in gas plumes of active volcanoes. The filters are quantitative for SO2 and the halide acids when sufficient base is present to neutralize the acidic species. Extremely high concentrations of SO2 may not be collected quantitatively since SO2 is a relatively weak Lewis acid compared to the halide acids. The acidic oxides of Sb, As, and Se were also collected quantitatively. A particle filter preceded the impregnated filters in order to remove particles from the fumes. This system has proven effective under difficult sampling conditions and, since it is portable and light weight, it could be used for many volcanological applications where high levels of acidic gaseous phase species need to be collected. 相似文献
300.
A. V. Mityukov A. M. Nikishin O. A. Almendinger S. N. Bolotov V. A. Lavrishchev N. K. Myasoedov E. V. Rubtsova 《Moscow University Geology Bulletin》2012,67(2):81-92
This work is based on the results of 2-D and 3-D surveys in the Tuapse Basin and field works in the Crimea-Caucasus region. Seven zones were outlined in the model of sedimentation starting from the eroded mountain structure of the Greater Caucasus down to deep water sediments of the Tuapse Basin. The slope and deep-water sediments of channels and fan complexes are characterized. Volume models of the sedimentation system in the Black Sea are shown for the first time. 相似文献