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21.
The changing chemical composition of cloud water and precipitation in the Western Sudety Mountains are discussed against the background of air-pollution changes in the Black Triangle since the 1980s until September 2004. A marked reduction of sulphur dioxide emissions between the early 1990's and the present (from almost 2 million tons to around 0.2 million tons) has been observed, with a substantial decline of sulphate and hydrogen concentration in cloud water (SO42− from more than 200 to around 70 μmol l− 1; H+ from 150 to 50 μmol l− 1) and precipitation (SO42− from around 80 to 20–30 μmol l− 1; H+ from around 60 to 10–15 μmol l− 1) samples. At some sites, where fog/cloud becomes the major source of pollutants, deposition hot spots are still observed where, for example, nitrogen deposition can exceed 20 times the relevant critical load. The results show that monitoring of cloud water chemistry can be a sensitive indicator of pollutant emissions. 相似文献
22.
Janusz Sylwester Zbigniew Kordylewski Stefan Płocieniak Marek Siarkowski Mirosław Kowaliński Stanisław Nowak Witold Trzebiński Marek Śtęślicki Barbara Sylwester Eugeniusz Stańczyk Ryszard Zawerbny Żaneta Szaforz Kenneth J. H. Phillips František Fárník Anatolyi Stepanov 《Solar physics》2015,290(12):3683-3697
23.
Ryszard Staroszczyk 《Acta Geophysica》2011,59(5):833-857
A multi-grain model for a migration recrystallization process in polar ice is presented. The model is based on the Sachs-Reuss
approximation of the stress homogeneity in a polycrystalline aggregate. An individual crystal of ice is treated as a transversely
isotropic and incompressible medium which deforms by viscous creep. The highly anisotropic viscous behaviour of the ice crystal
is described by a constitutive law expressing microscopic strain-rate in terms of the deviatoric stress and three fluidity
parameters that define different viscous resistances of the crystal in different glide directions. It is assumed that the
recrystallization occurs in those crystals in the aggregate which are most slowly deforming, and new crystals are nucleated
at orientations which favour the crystal deformation by basal glide. The model predictions are illustrated by results of numerical
simulations of simple flows, showing the evolution of the microscopic structure of ice and the variation of macroscopic viscosities
with increasing deformations. 相似文献
24.
Floods at the northern foothills of the Tatra Mountains — A Polish-Swiss research project 总被引:1,自引:1,他引:0
Zbigniew W. Kundzewicz Markus Stoffel Ryszard J. Kaczka Bartłomiej Wyżga Tadeusz Niedźwiedź Iwona Pińskwar Virginia Ruiz-Villanueva Ewa Łupikasza Barbara Czajka Juan Antonio Ballesteros-Canovas Łukasz Małarzewski Adam Choryński Karolina Janecka Paweł Mikuś 《Acta Geophysica》2014,62(3):620-641
The present paper introduces the topical area of the Polish-Swiss research project FLORIST (Flood risk on the northern foothills of the Tatra Mountains), informs on its objectives, and reports on initial results. The Tatra Mountains are the area of the highest precipitation in Poland and largely contribute to flood generation. The project is focused around four competence clusters: observation-based climatology, model-based climate change projections and impact assessment, dendrogeomorphology, and impact of large wood debris on fluvial processes. The knowledge generated in the FLORIST project is likely to have impact on understanding and interpretation of flood risk on the northern foothills of the Tatra Mountains, in the past, present, and future. It can help solving important practical problems related to flood risk reduction strategies and flood preparedness. 相似文献
25.
Metamorphosed volcanic and sedimentary successions in the central European Variscides are, in many areas, poorly biostratigraphically constrained, making palaeotectonic interpretations uncertain. In such instances, geochronological data are crucial. Sensitive high resolution ion microprobe (SHRIMP) dating of volcanic zircons from a quartz–white mica schist (interpreted as deformed metavolcaniclastic/epiclastic rock) within the stratigraphically controversial Wojcieszów Limestone of the Kaczawa Mountains (Sudetes, SW Poland), near to the eastern termination of the European Variscides, has yielded an age of 498 ± 5 Ma (2σ error), corresponding to late Cambrian to early Ordovician magmatism in that area and constraining the depositional age of the limestones. The new SHRIMP data are not consistent with the recent revision of the age of the Wojcieszów Limestone based on Foraminifera findings that ascribed them to a Late Ordovician—Silurian or even younger interval. They are though, consistent with sparse macrofossil data and strongly support earlier interpretations of the lower part of the Kaczawa Mountains succession as a Cambrian–Early Ordovician extensional basin‐fill with associated initial rift volcanic rocks, likely emplaced during the breakup of Gondwana. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
26.
Tomasz Janik Marek Grad Aleksander Guterch Ryszard Dadlez Jukka Yliniemi Timo Tiira G. Randy Keller Edward Gaczyski CELEBRATION Working Group 《Tectonophysics》2005,411(1-4):129-156
The large-scale CELEBRATION 2000 seismic experiment investigated the velocity structure of the crust and upper mantle between western portion of the East European Craton (EEC) and the eastern Alps. This area comprises: the Trans-European Suture Zone, the Carpathian Mountains, the Pannonian Basin and the Bohemian Massif. This experiment included 147 chemical shots recorded by 1230 seismic stations during two deployments. Good quality data along 16 main and a few additional profiles were recorded. One of them, profile CEL03, was located in southeastern Poland and was laid out as a prolongation of the TTZ profile performed in 1993. This paper focuses on the joint interpretation of seismic data along the NW–SE trending TTZ–CEL03 transect, located in the central portion of the Trans-European Suture Zone. First arrivals and later phases of waves reflected/refracted in the crust and upper mantle were interpreted using two-dimensional tomographic inversion and ray-tracing techniques. This modelling established a 2-D (quasi 3-D) P-wave velocity lithospheric model. Four crustal units were identified along the transect. From northwest to southeast, thickness of the crust varies from 35 km in the Pomeranian Unit (NW) to 40 km in the Kuiavian Unit, to 50 km in the Radom–Łysogóry Unit and again to 43 km in the Narol Unit (SE). The first two units are thought to be proximal terranes detached from the EEC farther to the southeast and re-accreted to the edge of the EEC during the Early Palaeozoic. The origin of the remaining two units is a matter of dispute: they are either portions of the EEC or other proximal terranes. In the area of the Polish Basin (first two units), the P-wave velocity is very low (Vp < 6.1 km/s) down to depths of 15–20 km indicating that a very thick sedimentary and possibly volcanic rock sequence, whose lower portion may be metamorphosed, is present. The velocity beneath the Moho was found to be rather high, being 8.25 km/s in the northwestern portion of the transect, 8.4 km/s in the central sector, and 8.1 km/s in the southeastern sector. 相似文献
27.
Crustal structure below the Polish Basin: Is it composed of proximal terranes derived from Baltica? 总被引:2,自引:2,他引:2
The large-scale seismic refraction and wide-angle reflection experiment POLONAISE'97 together with LT-7 and TTZ profiles carried out with the most modern techniques gave a high resolution of crustal structure of the Trans-European Suture Zone (TESZ) in NW and central Poland. The results of seismic investigations show the presence of relatively low velocity rocks (Vp < 6.1 km/s) down to a depth of 20 km beneath the Polish Basin (PB), and a high velocity lower crust (Vp = 6.8–7.3 km/s). The crustal thickness in the TESZ is intermediate between that of the East European Craton (EEC) to the northeast (40–45 km) and that of the Variscan crust (VB) to the southwest ( 30 km). Velocities in the uppermost mantle are relatively high (Vp = 8.25–8.45 km/s). The crust is three-layered with substantial differences in the velocities and thickness of individual layers. The area of the TESZ in NW and central Poland can be divided into at least two crustal blocks (terranes), called here Pomeranian Unit (PU, in the northwest) and Kuiavian Unit (KU, in the southeast). The postulated boundary between KU and PU is rather sharp at particular levels of the crust. Velocity distribution in the middle and lower crystalline crust in the TESZ area resemble values recognized in the EEC area, the fundamental difference being the much smaller thickness of both these layers. Our hypothesis/speculation is that the attenuated lower and middle crust of the TESZ belong to proximal terranes built of the EEC crust detached in the southeast and re-accreted to the EEC due to the process of anti-clockwise rotation of the Baltica paleocontinent during the Ordovician–Early Silurian. 相似文献
28.
Ryszard Błażejewski Jakub Nieć Sadżide Murat-Błażejewska Paweł Zawadzki 《水文科学杂志》2013,58(11):1707-1716
ABSTRACTGuidelines for the design of infiltration trenches of rectangular cross-section are compared. Four concepts of infiltration into a native soil from linear soakaways of rectangular cross-section are discussed. The results of calculations using analytical equations are compared with numerical two-dimensional (2D) simulations using HYDRUS computer code and field measurements. Satisfactory agreement is achieved for Kozeny’s concept of infiltration and the free-surface approach, applied to a trench in a highly saturated sandy loam. Theoretical solutions, neglecting matric potential, suggest that the mean infiltration rate along the wetted perimeter of a rectangular trench varies in the range 1.0 to 1.5 of the value of saturated hydraulic conductivity. 相似文献
29.
Teresa Oberc-Dziedzic Ryszard Kryza Ksenia Mochnacka Alexander Larionov 《International Journal of Earth Sciences》2010,99(1):27-46
Approximately 500-Ma-old orthogneisses are widespread in the eastern part of the Variscan belt and are commonly interpreted
to have intruded mica-schist series of assumed Neoproterozoic age. New SHRIMP zircon ages of quartzofeldspathic metavolcanogenic
rocks of the mica schist series in the eastern part of the Karkonosze-Izera Massif (SW Poland) indicate that they are late
Cambrian/early Ordovician rather than Neoproterozoic in age, based on the zircon age spectra distributed mainly between ca.
500 and 660 Ma (with a few Proterozoic inherited minimum ages of ca. 970 and 1,825 Ma). Younger zircon dates, dispersed between
ca. 412 and 464 Ma, are interpreted as a result of Pb-loss likely caused by subsequent metamorphism. Consequently, the felsic
metavolcanogenic rocks appear to be roughly contemporaneous with the intrusion of ca. 500-Ma-old orthogneiss protoliths (with
the pooled concordia age of 487 ± 8 Ma interpreted as the best approximation of the protolith intrusive age). Field relationships,
petrological and geochemical features of the felsic and mafic rocks studied support a model in which the accompanying mica
schist series are not the original country rocks to the ca. 500 Ma granite intrusions, and indicate that their recent close
proximity is the result of tectonic juxtaposition. However, both the mica schists enclosing the bimodal metavolcanic rocks,
and the orthogneisses, are interpreted to represent a Cambro-Ordovician passive continental margin sequence being part of
the Saxothuringian domain. They are tectonically overlain to the east by HP/T metamorphic units, comprising MORB-type metaigneous
rocks, and delineating a tectonic suture separating the Saxothuringian block in the west from an assumed continental block
(Tepla-Barrandian) to the south-east. 相似文献
30.
Artur Sobczyk Ryszard K. Borówka Janusz Badura Renata Stachowicz-Rybka Julita Tomkowiak Anna Hrynowiecka Joanna Sławińska Michał Tomczak Mateusz Pitura Mariusz Lamentowicz Piotr Kołaczek Monika Karpińska-Kołaczek Dariusz Tarnawski Marcin Kadej Piotr Moska Marek Krąpiec Krzysztof Stachowicz Bartosz Bieniek Krzysztof Siedlik Małgorzata Bąk Jan van der Made Adam Kotowski Krzysztof Stefaniak 《第四纪科学杂志》2020,35(4):539-558
The sedimentary succession exposed in the Gorzów Wielkopolski area includes Eemian Interglacial (MIS 5e) or Early Weichselian (MIS 5d–e) deposits. The sedimentary sequence has been the object of intense interdisciplinary study, which has resulted in the identification of at least two palaeolake horizons. Both yielded fossil remains of large mammals, alongside pollen and plant macrofossils. All these proxies have been used to reconstruct the environmental conditions prevailing at the time of deposition, as well as to define the geological context and the biochronological position of the fauna. Optically stimulated luminescence dating of the glaciofluvial layers of the GS3 succession to 123.6 ± 10.1 (below the lower palaeolake) and 72.0 ± 5.2 ka (above the upper palaeolake) indicate that the site formed during the Middle–Late Pleistocene (MIS 6 – MIS 5). Radiocarbon-dating of the lacustrine organic matter revealed a tight cluster of Middle Pleniglacial Period (MIS 3) ages in the range of ~41–32 ka cal bp (Hengelo – Denekamp Interstadials). Holocene organic layers have also been found, with 14C ages within a range of 4330–4280 cal bp (Neolithic). Pollen and plant macrofossil records, together with sedimentological and geochemical data, confirm the dating to the Eemian Interglacial. 相似文献