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Start Over Creator Antonín Zeman

2. Deformation between African and Eurasian plate estimated from the European and the Egyptian GPS geodetic networks results from preliminary processing

Creator:
Antonín Zeman, Hassan, Khalil, Holešovský, Jan, Mohamed, Abdel Monem S., Novotný, Zbyněk, Salah, Mahmoud M., Jan Kostelecký, and Ali, Radwan M.
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, GPS sítě, GPS netwoks, GPS coordinate time series, Egyptian GPS geodetic network, mechanics of continuum, deformation in the Eastern Mediterranean, 7, and 551
Language:
English
Description:
The article deals with estimating deformation between the African and the Eurasian Plate in the Eastern Mediterranean on the basis of GPS coordinate time series. Two sources of velocities were used for processing. The first was the freely available site velocities from the European Permanent Network (EPN). The second was the Egyptian GPS permanent network velocities. Their values were determined by the following technique. Firstly, the Egyptian site coordinates were computed from GPS daily observations, using the fiducial EPN stations. The daily site coordinates at a given time interval result in coordinate time series, which were analysed and used on velocity estimation of the Egyptian stations. Then the apparatus of the mechanics of continuum was applied to all resultant velocities. The regions of possible mutual interactions between the Eurasian and the African Plate in the Eastern Mediterranean were detected. The basic idea of this contribution is the common processing of GPS daily measurements from the Egyptian permanent network together with the EPN data. The available Egyptian GPS data cover almost the last three years, which represents a sufficient time interval for velocity estimation. Introducing the Egyptian permanent GPS measurements into processing enables a better estimate of deformations in the Eastern Mediterranean., Antonín Zeman, Khalil Hassan, Jan Holešovský, Abdel Monem S. Mohamed, Zbyněk Novotný, Mahmoud M. Salah, Jan Kostelecký and Radwan M. Ali., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Impact of Sumatra 2004 earthquake on geodynamic station GOPE (Czech Republic)

Creator:
Lukavec, Petr, Jan Kostelecký, Antonín Zeman, Jakub Kostelecký, Kouba, Jan, and Palinkáš, Vojtěch
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, GPS (navigační systém), GPS (navigation system), free oscillations, tidal gravimeter, PPP - Precise Point Positioning, spectral analysis, 7, and 551
Language:
English
Description:
The aim of this contribution is a detection of geodynamic effects at a very distant geodynamic station GOPE in the middle of Europe (Czech Republic). Strong earthquake, followed by strong indirect effect (tsunami), with the parameters (26.12.2004, 00:58:53.4 UTC, mag. 9.0, latitude 3.295N, longitude 95.982E, depth 30 km) was analysed from the records of tidal gravimeter (ASK No.228) with respect to free oscillations of the Earth (spheroidal component), by spectral analysis. This analysis detected significant vertical component of GOPE position in relatively long time interval (several hours) after the beginning of the earthquake. To verify the geodynamic tendencies of the GOPE station movements the GPS observations were analysed at the same time interval. We had data with 1s sampling interval at our disposal. For analysis we used PPP (Precise Point Positioning) method which produces absolute values of the coordinates in the ITRF 2000 system. Possible correlations between the results of both ways have been searched. We concentrated consequently to the determination of mean displacements and on the attempt of detection of some amplitudes of following free oscillations of the Earth. Mean change of position of the station GOPE during and after the earthquake, detected from the results of GPS observations is about 1.5 cm in horizontal and height components. Amplitude magnitudes for frequencies of the free oscillations of the Earth, which were analysed either from gravimetric data or from the GPS data, are equal in order. The study of free oscillations of the Earth by application of GPS is completely new. Studying of free oscillations is usualy accomplished by data from seismometers, tiltmeters or superconducting gravimeters., Petr Lukavec, Jan Kostelecký, Antonín Zeman, Jakub Kostelecký, Jan Kouba and Vojtěch Palinkáš., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public