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Start Over Creator Jan Kostelecký

2. Combination of different space geodesy techniques for EOP and terrestrial reference frame determination

Creator:
Štefka, Vojtěch, Jan Kostelecký, and Ivan Pešek
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodezie, geodesy, Earth orientation parameters, combination of space geodesy techniques, station coordinates, ITRF 2005, 7, and 551
Language:
English
Description:
The combination method of results of different space geodetic techniques gives two kinds of products. On the one hand, the Earth orientation parameters (EOP) that define the orientation of the Earth in space and, on the other, the coordinates of collocation stations by them the ITRF is realized. Obtained results are based on the method developed by authors, so called “non-rigorous” combination of the data. Approximately eight-year data was successively processed in order to obtain solutions of both products, which were then compared with the results given in ITRF 2005 solution., Vojtěch Štefka, Jan Kostelecký, and Ivan Pešek., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. 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

4. Detection of earth impact craters aided by the detailed global gravitational model EGM2008

Creator:
Jaroslav Klokočník, Jan Kostelecký, Pavel Novák, and Carl A. Wagner
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, gravitační odchylky, gravity anomalies, global gravitational model, second-order derivative of the disturbing potential, impact craters on the Earth, 7, and 551
Language:
English
Description:
We have surveyed the Earth's surface using gravity anomalies and second-order radial derivatives of the disturbing gravitational potential computed from the gravitational model EGM2008 complete to degree and order 2159 (for selected degrees up to 2190). It corresponds to 5 arcmin resolution on the ground. Over most well known impact crater sites on the Earth we found the second-order derivatives (not available from ordinary gravity surveys) offered finer discrimination of circular features than the gravity anomalies themselves. We also discovered that some of the sites show evidence of double or multiple craters which will need further ground verification. Some of these signatures (in hilly or mountainous terrain) may also need to be corrected for the gravitational effect of topography to sharpen their hidden features., Jaroslav Klokočník, Jan Kostelecký, Pavel Novák and Carl A. Wagner., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Earth orientation parameters and station coordinates from space geodesy techniques

Creator:
Štefka, Vojtěch, Ivan Pešek, Jan Vondrák, and Jan Kostelecký
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, tektonika, geotectonics, smoothing method, combination method, Earth orientation parameters, tectonic model NUVEL-1A, 7, and 551
Language:
English
Description:
The orientation of the Earth in space is measured by space geodetic techniques. Each technique has its weaknesses so the best way how to get a representative solution of Earth orientation parameters is to combine all of them together using some appropriate method. There are basically two approaches, the rigorous and non-rigorous one. The method used in this paper belongs to the second category. Since 1999, when the authors Kostelecký and Pešek put basis of the combination method, the method has been modified and improved. The particular improvements are described hereafter and recent results are presented. These results of collocation station velocities are compared with the velocities published by ITRF 2005 and NUVEL-1A. The mean values of differences are 2.7 mm/y and 5.9 mm/y, respectively., Vojtěch Štefka, Ivan Pešek, Jan Vondrák and Jan Kostelecký., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. Global and regional seasonal variations of the geoid detected by grace

Creator:
Jan Kostelecký, Aleš Bezděk, and Jaroslav Klokočník
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodynamika, geodynamics, GRACE mission, seasonal variations, eoid, 7, and 551
Language:
English
Description:
Since 2002, the US-German GRACE (Gravity Recovery and Climate Experiment) mission has been providing a precise survey of the Earth's time-variable gravity field, with unprecedented temporal and spatial sampling. GRACE time-variable gravity fields provide a means of measuring the temporal and spatial variations of mass redistribution within the Earth system. The GRACE mission has started a new era in studying a series of geophysical problems ranging from deep Earth structure to tracking mass redistribution on and near the surface of the Earth. Time variability of the gravity field presented here is based on the transformation of “monthly gravity field models” to the geoid. We show the changes caused by the global water cycle and land hydrology., Jan Kostelecký, Aleš Bezděk and Jaroslav Klokočník., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

7. 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

8. Motions and deformations of tectonic plates inferred from the ITRF 2005

Creator:
Šnajdrová, Miluše and Jan Kostelecký
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, geodezie, geodesy, plate tectonics, plate motion, horizontal surface deformation, ITRF 2005, 7, and 551
Language:
English
Description:
According to the theory of plate tectonics, the Earth crust is composed of 14 to 16 major independent segments - tectonic plates. These plates are in motion relative to one another. Not all the plate boundaries are exactly defined. The paper focuses on the behaviour of tectonic plates in the collision zones. Space geodesy techniques allow us to determine precise positions and velocities of the sites on the Earth surface. The global horizontal motions of the tectonic plates were derived from the coordinates and velocities of the stations defining the International Terrestrial Reference Frame - ITRF 2005 which is based on these techniques. The method described in (Kostelecký and Zeman, 2000) was employed. In the Mediterranean area, which is a contact area between the Eurasian, the Arabian and the African plate, also relative movements of the points located along the plate boundaries were computed. Further, a continuum mechanics approach was applied to detect surface deformations on the European continent and around collision zones between the tectonic plates all over the globe., Miluše Šnajdrová and Jan Kostelecký., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9. Results of geodetic measurements during the January 2010 efpalio earthquakes at the western tip of the Gulf of Corinth, Central Greece

Creator:
Jan Kostelecký and Jan Douša
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, zemětřesení, earthquake, Global Navigation Satellite System (GNSS),, 7, and 551
Language:
English
Description:
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
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public