Až do začiatku seizmometrických meraní, t.j. takmer do konca 19. storočia, boli účinky zemetrasení na ľudí, predmety, budovy a prírodu na danej lokalite, t.j. makroseizmické účinky, jedinými údajmi o zemetraseniach. Makroseizmické účinky je možné pozorovať vtedy, ak je lokálne magnitúdo zemetrasenia Ml>2.5 a ak sú kvantifikované pomocou makroseizmickej intenzity (1). Makroseizmická intenzita je určovaná v stupňoch makroseizmickej stupnice. Každý stupeň makroseizmickej stupnice je charakterizovaný súborom príznakov. Makroseizmická intenzita má teda charakter klasifikácie pozorovaných účinkov a škôd. Hodnoty makroseizmickej intenzity sú vyjadrené pomocou celých číseľ., Peter Labák., and Obsahuje seznam literatury
A collaborative group between Greek, Polish, and Sl ovak colleagues installed a dense network of non-permanent GPS stations and extensometers to monitor active faults in the eastern part of the Gulf of Corinth, central Greece. The network includes eleven GPS stations across the Kaparelli fault and the Asopos rift valley to the east and two TM-71 extensometers that were installed on the Kaparelli fault plane. So far the G PS network has been measured in three campaigns within the last three years with very good accuracies (1-4 mm in the horizontal plane). Although it is early to draw conclusions on the velocity field and on strain patterns it can be noted that, the data from the extensometers demonstrate both fault-normal opening and shear motion. Given that the total offset on the Ka parelli fault is small, and the geological data suggesting a segmented character of this fault, we expect in the near fu ture to differentiate fault slip and strain accumulation among segments., Athanassios Ganas, Jaroslaw Bosy, Lubomir Petro, George Drakatos, Bernard Kontny, Marian Stercz, Nikolaos S. Melis, Stefan Cacon and Anastasia Kiratzi., and Obsahuje bibliografické odkazy
The paper describes the results of Persistent Scatterers Interferometry (PSI) study of Sambia peninsula. The idea of this work was to verify the hypothesis whether any terrain surface deformation that occur in Sambia area, could be interpreted as related to tectonic processes. Moreover, if any movements are detected what is their relationship to the 21 September 2004 earthquake? To answer these questions SAR (Synthetic Aperture Radar) data from European satellites ERS-1 and ERS-2 acquired from 1992 to 2001 were processed with interferometric techniques to archive independent data about terrain surface deformation. The obtained results - 4 sets of PS (Persistent Scatterers) points with calculated movement velocities (mm/yr) according to linear model were compared with published results of terrestrial measurements. The analysis of PS results confirms the occurrence of terrain deformations of tectonic origin of few mm/yr. The distribution of deformation velocities suggest its relationship to the recent activity occurring along two E-W trending seismoactive sub-zones located along Pregola river valley and possibly in the northern coast of Sambia Peninsula., Zbigniew Perski and Marek Mróz., and Obsahuje bibliografii
Numerické metódy majú v skúmaní seizmického pohybu nezastupiteľnú a stále dôležitejšiu úlohu. Metóda konečných diferencií je v súčasnosti dominantnou metódou. Pokrok v jej aplikácii na seizmologické problémy súvisí s úsilím o realistickejšie modely a výpočtovú efektívnosť., Peter Moczo, Jozef Kristek., and Obsahuje seznam literatury
The Precise Point Positioning (PPP) analysis technique adapted for monitoring of moderate high-rate coordinate variations from GPS observations is applied for measuring actual displacements related to earthquakes. Two approaches are examined: kinematic PPP which is suitable for larger displacements and analysis of residuals from quasi-static PPP which is suitable for detection of minor displacements. Results from simulated horizontal movements of GPS antenna as well as analyses of 1 Hz GPS data from M 9.0 Sendai earthquake, M 6.3 L’Aquila earthquake and M 4.3 Tatabanya earthquake are shown. Our experiments proved the ability to measure dynamic seismic-related short-term coordinate variations at sub-centimetre level with PPP and to detect both strong and weak seismic signals using GPS satellites observations., Ján Hefty and Ľubomíra Gerhátová., and Obsahuje bibliografické odkazy
Micro-displacement monitoring in Slopy a nd Zbojnícka caves is described. It st arted at the end of 2005 with the use o f verified, stable and sensitive 3D crack gauges TM71 produced by GESTRA Sedloňov. Two gauges were installed in the caves across significant tectonic structures. Registered displacements are pertinent to the last significant earthquake events. The f irst one appeared in March 13, 2006 at Vrbové, M=3.2; and later in August 5-8, 2006, a swarm of 10 quakes M max = 2.2 at Trstín was registered. The results indicated trends of dextral strike-slip displacements across observed fault structures in both of those caves., Miloš Briestenský and Josef Stemberk., and Obsahuje bibliografické odkazy
The results of geodetic GNSS measurements on the EYPA station (bult by INSU CNRS from France) in Corinth Gulf in Greece are analyzed. Data is analyzed in the time interval before and after the earthquakes, which occured in January 2010. Results confirm vertical and horizontal co-seismic shifts of EYPA station of the order of 4 cm and 1 cm., Jan Kostelecký and Jan Douša., and Obsahuje bibliografické odkazy
We present first results of the study of possible relations between the seismic activity and crustal fluids (groundwater an d carbon dioxide) in the area of the Hronov-Poříčí Fault Zone (HPFZ), situated on the NE margin of the Bohemian Massif. Local seismic monitoring and observations of groundwater levels in deep wells and concentrations of carbon-dioxide in the mineral spring at Třtice was started in 2005. Since then, more than 30 local seismic events were observed in the area of the HPFZ. The two strongest earthquakes with macroseismic effects were recorded on August 10, 2005 (M = 2.4) and October 25, 2005 (M = 3.3). Most of the epicentres were situated along the central part of the HPFZ. Only some weak events from February and March 2006 were concentrated along the SE termination of the HPFZ. Results of the hydrological monitoring show that water level fluctuations are affected mainly by the precipitation, snow-melt, air pressure changes, and tidal deformations of the Earth’s crust. The effects of seismo-tectonic activity were detected only in one out of five water wells, where we observed several step-like water level anomalies with amplitudes of 4 to 15 cm. Two of them preceded the August 10, 2005 and October 25, 2005 earthquakes. Three other anomalies seemed to originate independently of the seismic activity. We therefore suppose that they were induced by aseismic movements along the HPFZ. Contrary to the water level fluctuations, CO2 concentrations in the mineral spring seem to be dependent on water temperature; no evident seismic-induced changes have been observed yet., Vladimír Stejskal, Lumír Skalský and Ladislav Kašpárek., and Obsahuje bibliografické odkazy
Před necelým půl rokem - 1. listopadu 2005 - vzpomněli přírodovědci na celém světě dvěstěpadesátého výročí nejsilnějšího evropského, tzv. velkého Lisabonského zemětřesení, při kterém na Iberském poloostrově zahynuly desítky tisíc lidí. V těchto dnech si připomínáme sté výročí jiné seismické katastrofy - nejničivější v historii celé Severní Ameriky -, zemětřesení, které dne 18. dubna 1906 devastovalo nejen město San Francisco v Kalifornii, ale i další sídliště v rozsáhlé přilehlé oblasti. and Jan T. Kozák.