The Geodynamic Network Sudety was joined to the Czech Gravity Reference Network (CGRN) by two weeks of the relative gravity measurements. The gravity stations of the CGRN were used as the anchor stations. There were used two relative gravimeters LaCoste & Romberg G. The method of measurement, used instruments, mathematical processing, variants of result computations and their accuracy are discussed., Petr Lukavec and Martin Lederer., and Obsahuje bibliografii
During 2007 and 2008 there were realized gravity measurements using the relative gravimeter Scintrex CG-5 on sites of geodynamic networks HIGHLANDS and fundamental gravity sites of the Czech Gravity Reference Network. The gravity measurements were concentrated on monitoring the long-term trends of gravity acceleration changes among individual measurement sites. The methodology of measurement was optimized and preliminary time changes in gravity differences among sites were determined., Roman Kujal, Vladimír Schenk and Zdeňka Schenková., and Obsahuje bibliografii
The western part of the Bohemian Massif (Vogtland/West-Bohemia region at the Czech-German border) is characterized by relatively frequent intraplate earthquake swarms and by other manifestations of current geodynamic activity, such as mofettes, mineral and thermal springs. In this study we analyze variations of groundwater level in four hydrological wells in the region during the years 2005-2010. Monitoring during the previous time interval of 2000-2004 is also mentioned and used for comparison. Two of the wells are located in the epicentral region of Nový Kostel, and the other wells are more distant. The time interval includes the 2008 earthquake swarm when all the wells displayed a noticeable drop in the water level. This effect was observed up to epicentral distances of nearly 30 km, which exceeds the distances of hydrological changes observed during previous earthquake swarms. Moreover, it seems that a small rise in the water level preceded the intervals of increased seismic activity, which could represent a certain precursory phenomenon. On the other hand, the hydrological changes in the Nový Kostel area were relatively small, indicating that this epicentral area is not hydrologically linked with the seismically active fault at depth. Consequently, more suitable localities for hydrological monitoring should be sought in a broader vicinity of Nový Kostel., Renata Gaždová, Oldřich Novotný, Jiří Málek, Jan Valenta, Milan Brož and Petr Kolínský., and Obsahuje bibliografii
In the West Bohemian region, Central Europe, the volcanic activity appeared in late Tertiary, the Miocene. The present intraplate magmatic activity makes itself felt by flows of gaseous and liquid fluids, enhanced geodynamic mobility of geological structures and generation of earthquake swarms. Position data of two permanent Global Navigation Satellite Systems (GNSS) stations located in the region were used to calculate the time variations of the horizontal strain field that were compared with the 3He/4He ratios and earthquake swarm occurrences. The strains and 3He/4He ratios displayed a positive relation supported by the earlier opinions on the dependence of the dynamics of the region on the fluid occurrence. Analysis of these quantities observed in 2006-2007 period indicated when the compressions calmed and the 3He/4He ratios grew then the earthquake events occurred. It presumes the detected variations relate to compressions and extensions in the region. The strain field changes monitored during the 2008 swarm proved the relation found above. The observed connections could be applied in future at selected regions in earthquake forecast procedures., Vladimír Schenk and Zdenka Schenková., and Obsahuje bibliografii
Presently the determination of the velocity field in the global reference frame is possible by using different space techniques and dense terrestrial networks from global to local and regional scales. However, the reliability of such determinations is strongly limited by the restricted number of unmodeled effects. Some of them are periodic (atmospheric or hydrological effects), some instantaneous (natural or man-made seismicity ) or seasons-related (snow cover, freezing). This elaboration deals with the unmodeled effects observed in the ASG-EUPOS (Polish Active Geodetic Network) time series. The whole network consists of over 130 permanent GNSS sites with different levels of stability. The paper presents the analysis of 3-year’s time-series of geodetic coordinates (in the topocentric projection) in order to obtain best-possible local velocity field. On the example of the Sudeten region, where 19 sites are located, the possible effects on the decrease in reliability of the velocity field determination are described. Finally the local velocity field in ITRF and ETRF frames are presented., Janusz Bogusz, Mariusz Figurski, Bernard Kontny and Piotr Grzempowski., and Obsahuje bibliografické odkazy
Non-liner inversion of ratio of (relative) P to S waves amplitudes of 3 selected KTB events was performed in Kolář (2007a) to determine moment tensors (MTs). Here further development of the method is presented: (i) re-calibration of the seismograms, (ii) re-interpretation of the S wave maximal amplitudes readings, (iii) a linear inversion of the (re-calibrated) amplitudes including MTs errors determination, and (iv) four methods of transformation of MT errors into errors of their decomposed parts. Generally, the new results confirm previous ones, however remain some open questions about MT errors transformation. New methodology is more accura te and data processing more user-friendly., Petr Kolář., and Obsahuje bibliografické odkazy
Chemical composition and structure of humic acids isolated from Cambisols forming on gneiss and amphibolite were studied. Cambisols differ in pH, cation exchange ca pacity, mineralogy composition, organic carbon input, plant residue and type of management. 13 C NMR and FTIR spectroscopy were used to show the main differences in humic substances quality. Humic acids isolated from soils developed on gneiss and amphibolite had wide variety of functional groups and different content of aromatic and aliphatic groups. Humic acids (HA) in arable soils contained more aromatic compounds and carbon in their molecule to compare with HA isolated from grassland. Forming of higher stability aggregates was connected with higher content of aliphatic groups in HA isolated from the grassland. Generally, humic acids in Cambisols represent young humic acids, with lower carbon content and high tendency to oxidation pr ocesses. Their chemical activity was mainly influenced by chemical composition and functional groups content., Ľubica Pospíšilová, Anna Žigová, Martin Šťastný and Tibor Liptaj., and Obsahuje bibliografické odkazy
The two stage co-pyrolysis method for obtaining of hydrogen is described. In the course of the heating of the mixture of bituminous coal with polyisoprene and styrene-butadiene polymers (co-pyrolysis), a considerable amount of hydrogen and hydrocarbons is released in dependence on the process conditions. The experiments proved that the amount of hydrogen increased already with slightly increased heating rate (5 K min-1 ) in comparison with the amount obtained at a common heating rate (3 K min-1) and, further, with the addition of the second (cracking) stage for further thermal splitting of release d hydrocarbons into hydrogen (and carbon), preferably at a temperature of 1200 ºC., Pavel Straka and Vlastimil Kříž., and Obsahuje bibliografické odkazy
by O. Nordgaard. The protist plankton and the diatoms in bottom samples / by E. Jørgensen., KČSN - signatura S-E 128, Poškozené desky., and Desky skenovány z jiné signatury. S-E 128