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Measuring magnetic properties of environmental samples
Zárubová, Alžběta ; Petrovský, Eduard (advisor) ; Kapička, Aleš (referee)
A. Zárubová: Měření magnetických vlastností environmentálních vzorků 1 ENGLISH ABSTRACT This bachelor's thesis presents briefly principles and examples of applications of magnetic measurements in environmental studies. Environmental magnetism is based on determination of iron oxides, their content, concentration and grain size. This information can be interpreted in terms of particle origin, transport or diagenesis. The results can provide information on, e.g., climatic changes in the past, short-term events influencing our environment (e.g., volcanic eruptions) or about contemporary problems associated with human activity (environmental pollution). In the last case, environmental magnetism does not intend to replace geochemical methods, but the main aim is to provide fast and easily available additional information, which helps us to be more effective in mapping contaminated areas, monitoring progression of pollution or modeling transport processes of contaminants. Magnetometry is currently intensively used for mapping contamination of atmosphere, soils and sediments; it can be used in defining long-term levels of contamination, individual pollution sources and their contribution to the overall pollution. This thesis provides a brief overview of the physical basics of environmental magnetism and examples...
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The basic composite section in the Barrandian Lower Devonian succession of the beds using magnetic susceptibility stratigraphy
Koptíková, Leona ; Hladil, Jindřich (advisor) ; Kapička, Aleš (referee) ; VerStraeten, Charles (referee)
The composite reference section in the Lower Devonian succession was established using the magnetic susceptibility (MS) and gamma-ray spectrometric (GRS) logs from 5 sections representing both deep- and shallow-water environment of carbonate slope systems in the Prague Synform. Both background data and data across the boundaries of geological units or event intervals were acquired with the emphasis on obtaining continuous data series. Such a complex, detailed and multidisciplinary data set (petrophysical, lithological, mineralogical and geochemical parameters) has never been collected here. They were linked to the existing biostratigraphical scales and offer complex information for interregional and global correlations now with the precision of a few centimetres, which is a resolution 10 to 100 fold higher than in any established biostratigraphic scale in the Devonian of the Prague Synform. Major changes in the MS, GRS logs and mineralogy concentrate to the proximity of the Lochkovian-Pragian boundary (close to the Lochkov-Praha Fm. boundary). At this level, a reversal point in Th/U ratios is observed (dominant Th concentrations in the Praha Fm. vs. dominant U concentrations in the underlying Lochkov Fm. and overlying Zlíchov Fm. There is a general transgressive trend for the Lochkov and Praha Fm....
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Methodology for evaluating the soil properties by using magnetic susceptibility , applicable for the assessment of soil degradation due to water erosion
Kapička, Aleš ; Kodešová, R. ; Jakšík, O. ; Klement, A. ; Petrovský, Eduard ; Grison, Hana
This work has been supported by the Ministry of Agriculture of the Czech Republic (Project No. QJ1230319, “Soil water regime within a sloping agricultural area”). The goal was to propose methodology for using the soil magnetic parameters for accessing soil properties and their spatial distribution within agricultural areas affected by water erosion. Methodology includes: choice of sampling design for target area (optimized based on other auxiliary data) and soil sampling (topsoil), soil sample processing (drying, grinding, sieving, etc.), method of magnetic susceptibility measurements (using Bartington MS2 and Kappametr SM400) and procedure to calibrate models of predicting soil properties from soil magnetic properties. Prediction of the oxidable organic carbon from the mass specific magnetic susceptibility determined in the laboratory is shown here as an example of practical application of this methodology for soil properties assessment in certain soil types. In addition close correlation between volume magnetic susceptibility measured directly in the field and mass specific magnetic susceptibility obtained in the laboratory documents that the oxidable organic carbon may be estimated directly from the field measurements.
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Komplexní analýza dlouhodobých změn krkonošské tundry: Komplexní geofyzikální výzkum a monitoring svahových pohybů na tundrových lokalitách v Krkonoších
Vysoké učení technické v Brně, Ústav geodézie ; Geofyzikální ústav AV ČR, Praha ; Univerzita Karlova v Praze, Přírodovědecká fakulta, Oddělení užité geofyziky, Praha ; Správa KRNAP, Vrchlabí ; Dvořák, Jan ; Weigel, Josef ; Kapička, Aleš ; Zima, Ladislav ; Vilhelm, Jan ; Kněz, Jaroslav ; Jáně, Zdeněk ; Dohnal, Jiří
Zpráva je syntézou prací na projektu Komplexní analýza dlouhodobých změn krkonošské tundry v rámci subprojektu 2, který byl zaměřen na využití geofyzikálních a geodetických metod včetně metody GPS k získání poznatků o strukturní stavbě a geologických vlastnostech prostředí zvětralinového pláště a jeho podloží se zřetelem na hydrologii.
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Fly-ash mobility in sandy material
Kodešová, R. ; Kapička, Aleš ; Fialová, Hana ; Žigová, Anna ; Kočárek, M. ; Kopáč, J. ; Petrovský, Eduard
Fly-ash migration in three sands of various particle size distributions and consequently various porosities was studied in the laboratory. The fly-ash was applied on the top of all sands packed in plastic cylinders followed by pulse infiltrations. Water regime was monitored using the soil water content sensors SM200 and micro-tensometers T5. Kappameter SM400 was used to monitor migration of ferrimagnetic particles-tracers presented in the fly-ash. Undisturbed samples of sands polluted by fly-ash were taken at the end of the experiments to study final fly-ash distribution in section planes and thin sections of sandy material.
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