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Start Over Subject geodynamics

1. 10th Czech-Polish Workshop on Recent Geodynamics of the Sudety Mts. and Adjacent Areas Szklarska Poreba, Poland, november 5 - 7, 2009

Creator:
Zdeňka Schenková and Vladimír Schenk
Format:
print, bez média, and svazek
Type:
article, zprávy, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, konference, geodynamics, conferences, Polsko, Poland, 7, and 551
Language:
English
Description:
Zdeňka Schenková and Vladimír Schenk.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. 12th Czech-Polish Workshop on Recent Geodynamics of the Sudety Mts. and Adjacent Areas Jugowice, October 20-22, 2011

Creator:
Zdeňka Schenková and Vladimír Schenk
Format:
print, bez média, and svazek
Type:
article, zprávy, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, konference, geodynamics, conferences, 7, and 551
Language:
English
Description:
Zdeňka Schenková and Vladimír Schenk. and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

4. A Method of forecasting earthquake by optical astronomic time-latitude residuals

Creator:
Su, Youjin, Gao, Yuping, and Hu, Hui
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
geodynamika, geomechanika, geofyzika, geologie, zemětřesení, geodynamics, geomechanics, geophysics, geology, earthquake, optical astronomic time-latitude residuals, change of the plumb line, motion of the groundmass, 7, and 551
Language:
English
Description:
This article reports a method for forecasting an earthquake by synchronous anomalies of optical astronomic time-latitude residuals. The so-called optical astronomic time-latitude residuals for a certain astrometric instrument are the rest after deducting the effects of Earth whole motion from the astronomical time and latitude observations determined by the instrument. Forecasting practice for four earthquakes around the Yunnan Observatory occurring after 2010 shows that it does not generate false forecasts, and also does not miss forecasts of major earthquakes. This forecasting practice proves that the synchronous anomalies of astronomical time-latitude residuals can provide effective warning sign for earthquake occurrence around observatory station, thus deserves attention and further study. and Su Youjin, Gao Yuping, Hu Hui.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

5. A model of rock mass fracturing ahead of the longwall face as a consequence of intensity of exploitation

Creator:
Drzewiecki, Jan and Makówka, Janusz
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, 7, and 551
Language:
English
Description:
In Czech and Polish underground hard coal mines of the Upper Silesian Coal Basin high-energy seismic phenomena are periodically recorded, the sources of which are located ahead of the longwall. Generally, these types of tremors are rooted in very strong, thick layers of sandstone, which are subject to the deformation border. The consequences are discontinuities and cracks with a range depending on the mechanical properties of destroyed rocks: the mechanical parameters of layers. Forecasting methods, developed in the Central Mining Institute, for stress concentration, seismic energy, fault zone and range, together with methods of rock fracturing using liquid or explosives, ,allow precise identification of suitable locations for controlled fracturing of rock mass with a pre-established direction. The size and range of discontinuities have an impact on mining parameters, dependent on basic exploitation intensity and expressed by the average daily progress of the longwall face. The rockmass is locally weakened because of exploitation or technical measures of discontinuities in the roof-rock on the longwall face. To prevent rockburst, measures are needed to reduce the amount of energy accumulating in the rockmass in the area of the longwall face. Knowledge of where stress is concentrated is extremely important for the development and implementation of effective preventative methods. For many years several research centres have been working on defining the range of these areas. In this paper, basic information is presented on methods developed by Central Mining Institute and used in Polish hard coal mines for forecasting energy concentration and assessing how it can be reduced., Jan Drzewiecki and Janusz Makówka., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. A new approach for the determination of onset of failure points during laboratory strength testing of rocks

Creator:
Mamurekli, Deniz
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, skály, geodynamics, rocks, pre-failure points, uniaxial tests, load-deformation, 7, and 551
Language:
English
Description:
Estimating the pre- failure points for rocks during laboratory testing is not a trivial task. In this study, a new approach is introduced that utilizes change in the slope of the load-deformation curves of rock in the loading cycle for marking the onset of failure point during uniaxial test of a given rock. At each step, load-deformation data footprints of the rock under test are inspected and a decision is made whether the failure has started or not. The load-deformation data obtained from different tests of different rocks are examined including; Norite, Granite, Limestone, Sandstone, Siltstone and Marble. The computational results over 154 cored rock samples show that the proposed approach locates the onset of failure point for a given rock with an acceptable degree of accuracy., Deniz Mamurekli., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

7. Accuracy of the relative gravity measurement

Creator:
Lederer, Martin
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, accuracy, precision, relative gravimetry, 7, and 551
Language:
English
Description:
Precise relative gravimeters achieve the internal precision about a few μGal 1, even in field conditions. Nevertheless this precision is in fact concerned with the instant of measurement and can not be confused with the accuracy of the gravity at the gravity station, which is influenced by other effects. The best approach of these two values is question of high-quality elimination of instrumental errors and time-variable disturbing effects affecting the relative gravity measurements., Martin Lederer., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Active tectonics in the Eastern Margin of the Bohemian massif: based on the geophysical, geomorphological and GPS data

Creator:
Lubomil Pospíšil, Pavel Roštínský, Otakar Švábenský, Josef Weigel, and Witiska, Michal
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, GPS (navigační systém), geodynamics, GPS (navigation system), active tectonic, morphology, movement tendencies, Waitzendorf and Diendorf faults, 7, and 551
Language:
English
Description:
One of the leaved out fault active systems at Southern Moravian can be considered the so called Diendorf - Čebín tectonic zone (DCTZ), that is seismically active in its southern segment (in Austrian). The Waitzendorf fault is a part of the DCTZ, with intensive morphological signs. The terrain recognizance along the eastern margin of the Dyje Dome confirmed many indi cations showing evidence of geodynamic activity. The facets, old land slides and rock falls indicate recent activity in the environs of Znojmo area. The paper offers interpretation of the geodetic results (GPS) using morphological and geophysical data from all area of the DCTZ ., Lubomil Pospíšil, Pavel Roštínský, Otakar Švábenský, Josef Weigel and Michal Witiska., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9. Advanced purification of industrial quartz using calcination pretreatment combined with ultrasound-assisted leaching

Creator:
Yang, Changqiao, Han, Shuaishuai, Li, Suqin, and Bai, Jiaxing
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
geodynamika, geomechanika, geofyzika, geologie, ultrazvuk, geodynamics, geomechanics, geophysics, geology, ultrasound, křemen, quartz, high purity quartz, iron removal, calcination pretreatment, gas-liquid inclusions, ultrasound-assisted leaching, 7, and 551
Language:
English
Description:
Purification of quartz using an environment-friendly method is important in the contaminants removal. This paper presents advanced method based on calcination pretreatment combined with ultrasound-assisted leaching, for removing iron impurities from industrial quartz. The solvent used is a mixture comprised by diluted hydrochloric acid and oxalic acid. The effects of experimental parameters were investigated and the purification mechanism was discussed using particle size analyzer, scanning electron microscope and polarized light microscope. SiO2 content of concentrate could be increased from 99.6828% to 99.9047%, which achieved 3N level high purity quartz, and Fe2O3 content reduced from 0.0857% to 0.0223%, under the optimal conditions, i.e., calcination temperature of 900 °C, holding time of 2 h, oxalic acid concentration of 10 g/L, hydrochloric acid concentration of 5%, liquid solid ratio of 5, leaching temperature of 60 °C, ultrasound power of 400 W and treatment time of 30 min. Compared to conventional method, the proposed method significantly accelerates the leaching process and increases the iron removal rate. At the same time, the method also can remove gas-liquid inclusions. and Yang Changqiao, Li Suqin, Bai Jiaxing, Han Shuaishuai.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

10. Amplitude spectra of surface waves generated by shot-hole explosions

Creator:
Holub, Karel
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, Rayleigh waves, shot-hole explosions, spectral analysis, amplitude spectra, 7, and 551
Language:
English
Description:
The object of the research was to investigate the spectral properties of Rayleigh-type surface waves, generated by shot-hole explosions during seismic refraction experiments which were carried out in the area of the Bohemian Massif and West Carpathians. The records of displacement amplitudes were spectrally analyzed and prevailing frequency fp, relative Δfr and absolute widths of the spectra Δfa were chosen as essential parameters. Whilst the prevailing frequencies were recorded within the interval f ÷ 0.80 - 3.70 Hz at the site of the observations, situated on the territory of the Bohemian Massif, the respecti ve frequency range f ÷ 0.80 - 2.6 Hz was found in the West Carpathians. Some functional dependences of the spectral amplitude parameters on epicentral distance were observed and regularities of their decrease were defined. Moreover, the influence of local seismogeological conditions at the shot point as well as at the site of observation occurred., Karel Holub., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public