Lidar observations of volcanic dust over Polish Polar Station at Hornsund after eruptions of Eyjafjallajökull and Grímsvötn     

Grzegorz Karasiński  Michał Posyniak  Magdalena Bloch  Piotr Sobolewski  Łukasz Małarzewski  Jakub Soroka 《Acta Geophysica》2014,62(2):316-339

Two significant volcanic eruptions, i.e., Eyjafjallajökull (April–May 2010) and Grímsvötn (May 2011) took place recently in Iceland. Within a few days after eruptions, layers of high aerosol concentration have been observed by multiwavelength lidar of the Polish Polar Station at Hornsund, Svalbard. Measurements of the aerosol’s optical properties indicated a possible presence of volcanic ash transported over the Station. The latter presumption was confirmed by the computed backward trajectories of air masses, showing their paths passing over the location of volcanoes.  相似文献   

Preliminary Results of Anthropogenic Seismicity Monitoring in the Region of Song Tranh 2 Reservoir,Central Vietnam     

Jan Wiszniowski  Nguyen Van Giang  Beata Plesiewicz  Grzegorz Lizurek  Dinh Quoc Van  Le Quang Khoi  Stanisław Lasocki 《Acta Geophysica》2015,63(3):843-862

Song Tranh 2 hydropower plant and the reservoir containing backed up water are located in the Quang Nam province (Central Vietnam). The region experiences unusual seismic activity related to the reservoir impoundment, with earthquakes of magnitude up to 4.7. In result of cooperation between the Institute of Geophysics, Vietnam Academy of Sciences and Technology and the Institute of Geophysics, Polish Academy of Sciences a seismic network has been built to facilitate seismic monitoring of the Song Tranh 2 area. The network, operating since August 2013, consists of 10 seismic stations. Here we show that the network is sufficient for advanced data processing. The first results of monitoring of the earthquake activity in Song Tranh 2 area in the period between 2012 and 2014, especially the completeness of catalogs, study and comparisons between water level and the seismic activity suggest direct connection between reservoir exploitation and anthropogenic seismicity.  相似文献   

A protoceratopsid skeleton with an associated track from the Upper Cretaceous of Mongolia     

Grzegorz Nied?wiedzki  Tomasz SingerGerard D. Gierliński  Martin G. Lockley 《Cretaceous Research》2012,33(1):7-10

The Djadokhta Formation of the Gobi Desert is known for the number and diversity of dinosaur and other vertebrate bones and skeletons found there, but only theropod, hadrosaur and supposed ankylosaurid footprints have been reported from this stratum. Dinosaur footprints are also noted from the Nemegt Formation, and occur as typical dinosaur track accumulations (tracksites). An articulated protoceratopsid skeleton - specimen ZPAL Mg D-II/3 - was collected by the Polish-Mongolian Expedition of 1965 from the Djadokhta Formation of Flaming Cliffs in Mongolia. Recently, the natural cast of a tetradactyl digitigrade footprint was found underneath the pelvic girdle while the skeleton and matrix were being prepared. This is possibly the first find of a dinosaur track in close association with an articulated skeleton. Although Protoceratops is an extremely common dinosaur in Mongolia, its footprints have never previously been reported from the Late Cretaceous of the Gobi Desert.  相似文献   

Density and magnetic models of the lithosphere along CELEBRATION 2000 profile CEL01     

Teresa Grabowska  Grzegorz Bojdys  Miroslav Bielik  Kristián Csicsay 《Acta Geophysica》2011,59(3):526-560

The paper presents 2D density and magnetic models of the crust and upper mantle along the DSS line profile of the CELEBRATION 2000 project that crosses the most important geological units in Central Europe. These are the Alps-Carpathians-Pannonian (ALCAPA) region, the SE part of the Paleozoic Platform (PLZ), the Trans-European Suture Zone (TESZ) and a fragment of the SW portion of the East European Craton (EEC). The density and magnetic models were constructed on the basis of a 2D model of P-wave velocity converted into density model, geological data as well as geothermal data and the results of integrated geophysical modelling for the lithosphere-asthenosphere boundary.  相似文献   

Interstellar CO towards X Persei (HD 24534) – II. Two-component model     

Grzegorz Kaczmarczyk 《Monthly notices of the Royal Astronomical Society》2000,316(4):875-884

The observations made by the Goddard High Resolution Spectrograph (GHRS) aboard the Hubble Space Telescope ( HST ) of molecular CO in absorbing gas towards X Persei are reported. The two-component statistical equilibrium model incorporating radiative excitation of CO by line emission at the same velocity that originates in nearby molecular clouds has been used to reproduce high-resolution GHRS spectra. Earlier analysis indicates that the cloud has a complex structure and at least a two-component model should be used to obtain accurate results. The spectra obtained from the International Ultraviolet Explorer ( IUE ) were used to complement GHRS data and constrain the space of possible solutions. The new oscillator strengths recommended by Eidelsberg et al. for A–X bands have been used. The results show that one of the components may be attributed to the Perseus OB2 molecular cloud, and the other component to an extension of the Taurus dark cloud. The total CO column density N (CO)=(1.0±0.2)×10¹⁶ cm⁻² has been determined. According to the results about 85 per cent of the observed CO belongs to an extension of the Taurus dark cloud. The CO radiation that originates in nearby molecular clouds may be the dominant excitation mechanism of the observed CO. The early results of ¹³CO line analysis indicate a ¹³CO/¹²CO ratio of about 40.  相似文献   

High‐precision U–Pb age and duration of the latest Devonian (Famennian) Hangenberg event,and its implications     

Paul M. Myrow  Jahandar Ramezani  Anne E. Hanson  Samuel A. Bowring  Grzegorz Racki  Michał Rakociński 《地学学报》2014,26(3):222-229

Precise U–Pb zircon dates from three volcanic ash beds that bracket the Hangenberg Shale in the Holy Cross Mountains, Poland, constrain the age and duration of one of the most significant palaeobiological events of the Palaeozoic Era, the Hangenberg Event. It is linked to a terminal Devonian global shift from greenhouse to icehouse climate conditions, a global transgression, and widespread black shale deposition. Our results constrain the Hangenberg Event to between 358.97 ± 0.11 Ma and 358.89 ± 0.20 Ma, with a calculated duration of 0.05 +0.14/?0.05 Ma. A third, underlying ash bed yielded a distinctly older age of 359.97 ± 0.46 Ma. The duration of ~50–100 ka. for the event is comparable to those of Quaternary glaciations, and is consistent with both a glacio‐eustatic origin for the eustatic fluctuations and changes in ocean chemistry that led to this major reorganization of the biosphere.  相似文献   

Sunshine duration and its variability in the main ridge of the Karkonosze Mountains in relation to with atmospheric circulation     

Urban  Grzegorz  Migała  Krzysztof  Pawliczek  Piotr 《Theoretical and Applied Climatology》2018,131(3-4):1173-1189

Theoretical and Applied Climatology - Sunshine duration analysis was based on a series of measurements spanning the period from 1901 to 2014 for Śnieżka (1603 m a.s.l.)...  相似文献   

Characteristics of mining tremors within the near-wave field zone     

Józef Dubiński  Grzegorz Mutke 《Pure and Applied Geophysics》1996,147(2):249-261

Mining in the Upper Silesian Coal Basin, Poland, induces tremors with magnitudes ranging up to 4.3. The recordings of mining tremors from the near-wave fiel and the far-wave field show different characteristics of ground motion.Knowledge of these characrteristics, has an enormous practical importance when solving the problems of resistance of underground workings against seismic impacts. The near-wave field is characterized by a domination of the high frequency components of motion, and the seismograms often are a single pulse Geomechanical interpretation of them leads to the conclusion that this pulse corresponds to a single exciting force. This fact is also reflected in the rockbursts: the potentially damaging ground motion which is restricted to the seismic source region.The seismometric data have shown that the peak particle velocities from a hypocentral distance of 200–300 m, resulted in more than 3 cm/s. The peak ground velocities appear to be dependent on stress drop , and peak particle velocities reaching 5 m/s may occur. The computational example proves that in a thick coal seam the pulse with the stress =1.8 MPa from the tremor at the short source distance can generate the rockburst.  相似文献   

Long-term air temperature variation in the Karkonosze mountains according to atmospheric circulation     

Krzysztof Migała  Grzegorz Urban  Karol Tomczyński 《Theoretical and Applied Climatology》2016,125(1-2):337-351

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Compressibility and permeability of sand–kaolin mixtures. Experiments versus non‐linear homogenization schemes     

Claude Boutin  Grzegorz Kacprzak  Doanh Thiep 《国际地质力学数值与分析法杂志》2011,35(1):21-52

This study deals with the behaviour of mixtures of sand and saturated kaolin paste considered as composite materials made of permeable and deformable (with non‐linear behaviour) matrix (the kaolin paste) with rigid and impervious inclusions (the sand grains). Oedometric and permeability tests highlight the key role of the state of the clay paste, and show the existence of a threshold of sand grain concentration above which a structuring effect influences both compressibility and permeability. At the light of these experiments two homogenization schemes (with simplifying assumptions to make the problem manageable) are considered to model these two parameters. Qualitative and quantitative comparisons with experimental data point out their respective domain of interest and limitations: a tangent homogenization scheme is shown to be sufficient to describe the macroscopic properties for dilute sand concentration; above the concentration threshold, the structuring effect is captured by the new homogenization scheme developed in this paper. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献