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51.
Mariusz Białecki 《Acta Geophysica》2015,63(4):923-956
Finite version of Random Domino Automaton — a recently proposed toy model of earthquakes — is investigated in detail. Respective set of equations describing stationary state of the FRDA is derived and compared with infinite case. It is shown that for a system of large size, these equations are coincident with RDA equations. We demonstrate a non-existence of exact equations for size N ≥ 5 and propose appropriate approximations, the quality of which is studied in examples obtained within the framework of Markov chains.We derive several exact formulas describing properties of the automaton, including time aspects. In particular, a way to achieve a quasi-periodic like behaviour of RDA is presented. Thus, based on the same microscopic rule — which produces exponential and inverse-power like distributions – we extend applicability of the model to quasi-periodic phenomena. 相似文献
52.
Maria Fajer Jan Maciej Waga Mariusz Rzetala Artur Szymczyk Ma?gorzata Nita Robert Machowski Martyna A. Rzetala Marek Ruman 《Journal of Paleolimnology》2012,48(4):651-667
Jezioro Lake is the only natural lake in southern Poland outside mountainous areas to have existed continuously since the Pleistocene. The record of environmental change in the Late Vistulian (Weichselian) and Holocene is preserved in the deposits and landforms around the lake. This paper presents the results of paleogeographical and paleoecological research that emabled us to reconstruct the history of the Jezioro Lake. At the end of the Vistulian period, the outlet of the lake was blocked by a parabolic dune moving in from the west. Limnic sedimentation was evident in the sediment core at all levels from the Holocene, with remains of Cladocera, Chironomidae larvae, and aquatic plants. The lake did not disappear at that time, although its area decreased by a factor of 12 by the end of the period. Paleobotanical research permitted the reconstruction of sequences of plant communities and changes in nutrient status and water level. An initial oligotrophic lake, as indicated by the presence of Iso?tes lacustris L., changed to a eutrophic lake, as indicated by the presence of Potamogeton natans L. and Nuphar sp., then the lake progressed to the present-day dystrophic lake that is surrounded by a swamp. The profile of organic deposits contains a record of environmental change at least since the Younger Dryas in southern Poland. 相似文献
53.
Mariusz J. Rospondek Leszek Marynowski Anna Chachaj Maciej Gra 《Organic Geochemistry》2009,40(9):986-1004
Numerous reports have recognised the presence of compounds with molecular weight 254 a.m.u. in aromatic fractions. However, their unequivocal identification has not been achieved due to a lack of reference substances. In geological samples, such m/z 254 compounds could potentially be represented by a number of structural isomers of binaphthyl, phenylphenanthrene, phenylanthracene and indenofluorene with each compound type possessing several positional isomers. In this work, all these m/z 254 compounds, with the exception of the tentatively recognised indenofluorenes, have been unequivocally identified in sedimentary rocks for the first time. Comparison of the mass spectra and the gas chromatography (GC) retention times of synthesised standards with the natural compounds in rocks shows that the major components of aromatic fractions are phenylphenanthrene isomers and, to a lesser extent, binaphthyls and 9-phenylanthracene. The elution sequence expressed as standard retention indices of all these m/z 254 isomers were determined by using high resolution capillary GC with three stationary phases: 5%, 35% and 50% (mole fraction) phenyl substituted methylpolysiloxane on HP-5MS, DB-35MS and DB-17MS columns, respectively. A survey of more than 350 sedimentary rock samples of varying origins and maturity (Rr 0.3–1.4%) reveals that relative abundances of the m/z 254 isomers depend on the maturity of the organic matter. The isomers initially appear at the onset of oil generation (Rr > 0.5%) exclusively in diagenetically/catagenetically oxidised samples containing varying proportions of Types II and III kerogen. Interestingly, all five possible positional phenylphenanthrene isomers (including the most sterically hindered isomer 4-phenylphenanthrene) are present from the beginning of the oil generation window. Such a distribution suggests that low-regioselectivity reactions are likely to be involved in the formation. Interaction, during maturation, of phenyl radicals from primary cracking with aromatic moieties of more resistant terrigenic components of kerogen in an oxidising diagenetic realm is postulated to be responsible for the neoformation of phenylated aromatics in geological samples. Up to the final stages of oil generation, the evolution of the phenyl PAH distributions presumably involve 1,2-phenyl shift reactions and cyclisation, if allowed by the molecular geometry. A near thermodynamically-controlled distribution, with only 3- and 2-phenylphenanthrene and minor 2,2′-binaphthyl remaining, is approached when vitrinite reflectance reaches 1.2% (Rr). The three compounds seem to be persistent beyond the oil window as is suggested by their presence in hydrothermal oil formed at T > 300 °C. 相似文献
54.
Rockfalls are major natural hazards in mountainous regions and as such monitored if they pose a high risk to people or infrastructure. Ground-based radar interferometry is a relatively new technique suitable for such monitoring. It offers the potential for determining sub-mm- to mm-level displacements by remote measurements under various weather conditions. To avoid damage from smaller rocks and debris, critical surfaces are often protected by rockfall catch fences. We present an experimental investigation proving that the radar measurements are indeed significantly affected by a catch fence made of steel even if its mesh size is larger compared to that of the wavelength of the radar. A stable rock wall in a quarry was monitored by means of a ground-based synthetic aperture radar for 2 days. Different fences varying in shape, size, and density of mesh and in various geometrical configurations were erected at different locations for short periods of time during the experiment. We show that for surfaces observed through the fence, the reflected power can be reduced by 20 dB and thus the signal-to-noise ratio is significantly deteriorated. We also observed spurious interferometric phase shifts. Even parts of the rock wall not covered by the fences are affected. Side lobes and mixed pixels result, e.g., in severe loss of coherence and thus potentially mask actual displacements. 相似文献
55.
The influence of industrial immissions on the magnetic susceptibility of soils in upper Silesia 总被引:4,自引:0,他引:4
Zygmunt Strzyszcz Tadeusz Magiera Friedrich Heller 《Studia Geophysica et Geodaetica》1996,40(3):276-286
Summary Samples of metallurgical dusts and fly ashes from coal power plants and iron works in Upper Silesia as well as soil profiles
in the close vicinity of these plants and in Ojcow National Park (ca. 25 km east of the industrial area) have been studied
magnetically and mineralogically. The metallurgical dusts and fly ashes are highly enriched in ferromagnetic minerals. The
topsoils from profiles collected near the plants have very high values of magnetic susceptibility while susceptibility in
the fermentation and humic subhorizons in soil profiles from Ojcow National Park is considerably increased. The magnetic properties
of the metallurgical dusts and fly ashes such as frequency dependence of susceptibility, saturation remanence or coercivity
are similar to those observed in the top horizons of the soils. They are mostly related to the occurrence of large (multidomain)
grains of non-stoichiometric magnetite ranging from 1 to 20 μm. The similarity of the magnetic particles in the soils is taken
as evidence of an anthropogenic origin. They are responsible for the high soil susceptibilities in Upper Silesia and in adjacent
areas. Some of the magnetic particles carry substantial quantitities of trace elements such as Pb, Ni, Zn and Cu. Field and
laboratory susceptibility measurements can therefore be used as a simple and costeffective method of detecting the presence
of heavy metals in the soils of this area. 相似文献
56.
2-D seismic tomographic and ray tracing modelling of the crustal structure across the Sudetes Mountains basing on SUDETES 2003 experiment data 总被引:2,自引:3,他引:2
Mariusz Majdaski Marek Grad Aleksander Guterch SUDETES Working Group 《Tectonophysics》2006,413(3-4):249-269
The seismic data obtained during SUDETES 2003 experiment are analysed, and detailed crustal structure for profiles S02, S03 and S06 is presented using three different 2-D techniques: (1) “smooth” tomography of refracted waves travel times, (2) ray tracing of reflected and refracted waves, and (3) joint velocity and depth of reflector tomographic inversion. In spite of different interpretation techniques used, the models of the crustal structure show common characteristic features. The low velocity (Vp < 4 km/s) sedimentary layer was documented in the northeastern part of the study area. The topmost basement has in general a velocity of 5.8–6.0 km/s, and velocities at ca. 20 km depth are 6.15–6.25 km/s. The strong reflecting boundaries were found at 20–23 and 25–28 km depth with a velocity contrast about 0.4 km/s, and the highest velocities in the lowermost crust are 6.8–7.2 km/s. In general, the crust of the Bohemian Massif is slightly thicker (33–35 km) than in the northern part of the area. Velocities beneath Moho are relatively low, of 7.95 km/s. On the basis of well recorded reflected waves, mantle reflectors were discovered in the depth interval ca. 40–70 km. Apart of new results for the geology and tectonics of the area, some conclusion could be made about different techniques used. In the 2-D case the “clasical” ray tracing method with using all correlated phases gives the most adequate model of the structure, because of full, manual control of the model creation. The “smooth” first arrival travel times tomography, although very fast, is not satisfactory enough to describe the complex structure. So, the best candidate in 3-D case seems to be travel time tomography for both refracted and reflected waves in multi-layers models. 相似文献
57.
Zygmunt Kowalik William Knight Tom Logan Paul Whitmore 《Pure and Applied Geophysics》2007,164(2-3):379-393
A numerical model for the global tsunamis computation constructed by Kowalik et al. (2005), is applied to the tsunami of 26 December, 2004 in the World Ocean from 80°S to 69°N with spatial resolution of one
minute. Because the computational domain includes close to 200 million grid points, a parallel version of the code was developed
and run on a Cray X1 supercomputer. An energy flux function is used to investigate energy transfer from the tsunami source
to the Atlantic and Pacific Oceans. Although the first energy input into the Pacific Ocean was the primary (direct) wave,
reflections from the Sri Lankan and eastern shores of Maldives were a larger source. The tsunami traveled from Indonesia,
around New Zealand, and into the Pacific Ocean by various routes. The direct path through the deep ocean to North America
carried miniscule energy, while the stronger signal traveled a considerably longer distance via South Pacific ridges as these
bathymetric features amplified the energy flux vectors. Travel times for these amplified energy fluxes are much longer than
the arrival of the first wave. These large fluxes are organized in the wave-like form when propagating between Australia and
Antarctica. The sources for the larger fluxes are multiple reflections from the Seychelles, Maldives and a slower direct signal
from the Bay of Bengal. The energy flux into the Atlantic Ocean shows a different pattern since the energy is pumped into
this domain through the directional properties of the source function. The energy flow into the Pacific Ocean is approximately
75% of the total flow to the Atlantic Ocean. In many locations along the Pacific and Atlantic coasts, the first arriving signal,
or forerunner, has lower amplitude than the main signal which often is much delayed. Understanding this temporal distribution
is important for an application to tsunami warning and prediction. 相似文献
58.
Mariusz Tarnopolski 《Celestial Mechanics and Dynamical Astronomy》2017,127(2):121-138
The gravitational influence of a second satellite on the rotation of an oblate moon is numerically examined. A simplified model, assuming the axis of rotation perpendicular to the (Keplerian) orbit plane, is derived. The differences between the two models, i.e. in the absence and presence of the second satellite, are investigated via bifurcation diagrams and by evolving compact sets of initial conditions in the phase space. It turns out that the presence of another satellite causes some trajectories, that were regular in its absence, to become chaotic. Moreover, the highly structured picture revealed by the bifurcation diagrams in dependence on the eccentricity of the oblate body’s orbit is destroyed when the gravitational influence is included, and the periodicities and critical curves are destroyed as well. For demonstrative purposes, focus is laid on parameters of the Saturn–Titan–Hyperion system, and on oblate satellites on low-eccentric orbits, i.e. \(e\approx 0.005\). 相似文献
59.
Study of litter influence on magnetic susceptibility measurements of urban forest topsoils using the MS2D sensor 总被引:1,自引:1,他引:0
Jarosław Zawadzki Piotr Fabijańczyk Tadeusz Magiera Zygmunt Strzyszcz 《Environmental Earth Sciences》2010,61(2):223-230
Field magnetometry is fast and convenient method used to detect areas contaminated by technogenic magnetic particles and potentially
polluted with heavy metals. Frequently, measurements of soil magnetic susceptibility (κ) are carried out with MS2D Bartington
sensor, which penetration range equals 10 cm, although 90% of the total signal is detected from a depth of up to 6 cm. Thick
uppermost organic soil layers may significantly influence on the measured κ because the penetration range may be not large
enough to cover the layers where the most of anthropogenic contaminants are cumulated. The aim of the study was to investigate
on how the removal of the litter improves the MS2D measurements of soil pollution. Accordingly, the correlations between κ
values measured on the successively removed overlying soil sub-horizons were investigated. Measurements were performed at
15 sites located in different forest in the Upper Silesian Industrial Area, Poland. The results showed that the litter removal
enabled the MS2D to measure the κ more related to the anthropogenic pollution, and did not affect the measuring variance. 相似文献
60.
Geographically weighted regression algorithm (GWR) has been applied to derive the spatial structure of urban heat island (UHI) in the city of Wroc?aw, SW Poland. Seven UHI cases, measured during various meteorological conditions and characteristic of different seasons, were selected for analysis. GWR results were compared with global regression models (MLR), using various statistical procedures including corrected Akaike Information Criterion, determination coefficient, analysis of variance, and Moran’s I index. It was found that GWR is better suited for spatial modeling of UHI than MLR models, as it takes into account non-stationarity of the spatial process. However, Monte Carlo and F3 tests for spatial stationarity of the independent variables suggest that for several spatial predictors a mixed GWR–MLR approach is recommended. Both local and global models were extended by the interpolation of regression residuals and used for spatial interpolation of the UHI structure. The interpolation results were evaluated with the cross-validation approach. It was found that the incorporation of the spatially interpolated residuals leads to significant improvement of the interpolation results for both GWR and MLR approaches. Because GWR is better justified in terms of statistical specification, the combined GWR?+?interpolated regression residuals (GWR residual kriging; GWRK) approach is recommended for spatial modeling of UHI, instead of widely applied MLR models. 相似文献