K poznání podpovrchových partií zemského tělesa lze přispět jednak nepřímo - extrapolací povrchových geologických měření a pozorování, interpretací geofyzikálních a geodetických měření či využitím výsledků laboratorních experimentů, jednak přímo - pomocí hlubokých vrtů do svrchních partií zemské kůry. Metoda hlubokého vrtání má sice řadu nevýhod (vysoká cena; získaná informace je vztažena k jedinému bodu na zemském povrchu a její zobecnění je tudiž problematické), omezení (maximální dosažená hloubka 12262 m v r. 1989 na poloostrově Kola v Rusku; v České republice 6506 m v r. 1982 v moravské části vídeňské pánve - [1]) a provázejí ji mnohá technologická úskalí (vysoká teplota a tlak ve velkých hloubkách), je však neodmyslitelnou součástí výzkumu zemského tělesa jako korektiv geologických a geodynamických modelů, vycházejících z nepřímých pozorování a jejich interpretace., Aleš Špičák., and Obsahuje seznam literatury
Diatomite is a siliceous sedimentary rock, and it can be used in many industrial applications due to its high porosity, low density porous and permeable structure, chemical resistance, high purity, high specific surface area, absorptive capacity and to its absorbent properties. The best known Portuguese occurrences of diatomite are located in the regions of Óbidos and Rio Maior. The purpose of this research is to characterize the Rio Maior and Amieira diatomite and beneficiate this rock to be used in some potential applications locally or not. The studied diatomites present a fine texture; chemically the samples have a high SiO2 content, the principal minerlas are quartz and amorphous opal. The studied diatomites benefited with temperature and addition of NaCl (acting as accelerator of the crystallization process), with 5 % of NaCl being reduced the transformation temperature of the amorphous opal in opal C / CT at about 200 ºC. The diatomites from Rio Maior and Amieira in natural state has an enormous potential as absorbent, of heavy metals (e.g. in soil contamination) or dyes (textile industry). These diatomites after beneficiation can be used in construction materials (as additive), being more reactive and crystalline than in the natural state, diatomites can be promoters of mechanical resistance in mortars and geopolymers. and Costa Cristiana, Velosa Ana, Cerqueira Angela, Caetano Paulo, Rocha Fernando.
Set of events from West Bohemian 2008 seismic swarm with known source mechanisms is processed. The events or their slips respectively are clustered into two groups: (i) principal events with slip laying in the main fault plane and (ii) complementary events deviating from that plane. From those slips we constructed image of slip distribution (a new way of data/slip presentation) and from slip distribution and variations we hypothesized about foci zone properties. Namely, we propose that western block is more rigid and compact; the eastern block appears to be constituted from several sub blocks which can interact with each other during the swarm course. Our hypothesis is supported by similar image constructed from relative rupture velocities, which we consider as independent data. The proposed structural model agrees with the existence of the different observed types of source mechanisms. and Kolář Petr, Boušková Alena.
Celestial pole offsets are the displacements between the observed position of the Earth’s spin axis in space and its position predicted by the adopted models of precession and nutation. At present, the models are IAU2006 and IAU 2000, respectively. The celestial pole offsets are regularly measured by Very Long-Baseline Interferometry (VLBI), the observations being coordinated and published by the International VLBI Service for Geodesy and Astrometry (IVS). These offsets contain a mixture of several effects: the unpredictable free term, Free Core Nutation (FCN) that is due to the presence of the outer fluid core of the Earth, forced motions excited by the motions in the atmosphere and oceans, and also imperfections of the adopted precession-nutation models. The geophysical excitations are also available, as determined by several atmospheric and oceanographic services. The aim of this paper is to compare the time series of these integrated excitations with the observed celestial pole offsets and estimate the level of coherence between them., Cyril Ron and Jan Vondrák., and Obsahuje bibliografii