Aim. This article analyses the modern usage of GNSS data for solving problems in geodynamics and examines the level of data suitability for estimation of regional motion and deformations of the Earth’s surface according to their accuracy and the overall time of observation during which the representative estimation results can be provided. Method. This research was prompted by the following factors: absence of clearly established motion parameters of lithospheric plates; different strategies in processing observations and related software; unregulated minimum duration of observations; the need to increase the density of the area coverage; the need to use numerous stations for specification of tectonic models, deformation analysis, area zoning, and identification of anomalous zones of potentially dangerous geological processes. As input data, we chose three public bases of time coordinate series of stations within the Eurasian plate in Europe that are in the SOPAC archive: SIO database, formed as a result of processed observations in GAMIT-GLOBK (177 stations), and two JPL databases (204 stations) where coordinate series are obtained by processing observations using GIPSY-OASIS and combined QOCA-solution. Subject to empirical investigation for each database were coordinate series during the period 1.01.2005-1.01.2015 with a one month sampling interval. The experiment aimed at determining such integrated motion parameters of the surface under study like the weighted arithmetic linear offsets, vector length and direction, and velocity. These parameters are computed for all stations after their culling according to two formal representativeness criteria: 1) absolute values of stations offsets are greater than their average squared errors; 2) absolute values of an offset are greater than their marginal errors. According to these criteria, we determined stations that were culled most often and, thus, needed to thoroughly and individually analyzed during their usage for the purposes of geodynamics. Results. The experiment results showed that the minimal duration of observations is not constant and must be determined for each set of empirical data. According to the most optimistic estimates, the millimeter accuracy of motion parameters computation can be achieved after more than 2.5 years observation and usage of coordinate time series of the JPL (QOCA) database. This period is achieved using both criteria for culling of the observation period of 2005-2008 that approximately fits the limits of the official ITRF version. The centimeter accuracy under the same conditions can be achieved after more than 0.8 of a year. For the entire 10 year research period, the specified periods are more than doubled. The only explanation for such considerable differences is that they are the consequence of the motion and unadjusted position of the origin of the ITRS. The scientific novelty and practical significance. The obtained results indicate that there is a need to introduce a modern ITRF and to adjust the position of the origin more frequently. If the specified minimal periods are adhered to, the culling according to the marginal criterion is inappropriate because as a result many stations are discarded. The experiment results proved the advantages of QOCA solutions in terms of usage of the obtained coordinate time series comparing to GIPSY-OASIS and GAMIT-GLOBK.
1. Altamimi Z., Sillard P., Boucher C. ITRF2000: A new release of the International Terrestrial Reference Frame for earth science applications. J. Geophys. Res. 2002, Vol. 107(B10), No 2214, 19. doi: 10.1029/2001JB000561
https://doi.org/10.1029/2001JB000561
2. Altamimi Z., Collilieux X., Legrand J., Garayt B., Boucher C. ITRF2005: A new release of the International Terrestrial Reference Frame based on time series of station positions and Earth Orientation Parameters. J. Geophys. Res. 2007, Vol. 112(B9), No B09401, 19. doi: 10.1029/2007JB004949
https://doi.org/10.1029/2007JB004949
3. Altamimi Z., Collilieux X., Metivier L. ITRF2008: an improved solution of the international terrestrial reference frame. J. Geod. 2011, Vol. 85(8), 457–473. doi: 10.1007/s00190-011-0444-4
https://doi.org/10.1007/s00190-011-0444-4
4. Altamimi Z., Metivier L., Collilieux X. ITRF2008 plate motion model. J. Geophys. Res. 2012, Vol. 117(B7), No B07402, 14. doi: 10.1029/2011JB008930
https://doi.org/10.1029/2011JB008930
5. Altamimi, Z., Rebischung, P., Metivier, L., Collilieux, X., ITRF2014: a new release of the international terrestrial reference frame modeling nonlinear station motions. J. Geophys. Res. 2016, Vol. 121(B8), 6109–6131. doi: 10.1002/2016JB013098
https://doi.org/10.1002/2016JB013098
6. Altiner Y., Bacic Z., Basic T., Coticchia A., Medved M., Mulic M., Nurce B. Present-day tectonics in and around the Adria plate inferred from GPS measurements. In: Dilek Y., Pavlides S. (Eds.) Postcollisional tectonics and magnetism in the Mediterranean region and Asia. Geological Society of America Special Paper, 2006, No. 409, 43–55.
https://doi.org/10.1130/2006.2409(03)
7. Argus D. F., Gordon R. G., DeMets C. Geologically current motion of 56 plates relative to the no-net-rotation reference frame. Geochemistry, Geophysics, Geosystems. 2011, Vol. 12(11), No Q11001, 13. doi: 10.1029/2011GC003751
https://doi.org/10.1029/2011GC003751
8. Argus D. F., Gordon R. G., Heflin M. B., Ma C., Eanes R., Willis P., Peltier W. R., Owen S. E. The angular velocities of the plates and the velocity of Earths centre from space geodesy. Geophys. J. Int. 2010, Vol. 180(3), 913–960. doi: 10.1111/j.1365-246X.2009.04463.x
https://doi.org/10.1111/j.1365-246X.2009.04463.x
9. Bird P. An updated digital model of plate boundaries. Geochemistry, Geophysics, Geosystems. 2003, Vol. 4(3), No 1027, 52. doi: 10.1029/2001GC000252
https://doi.org/10.1029/2001GC000252
10. DeMets C., Gordon R.G., Argus D.F., Stein S. Current plate motions. Geophys. J. Int. 1990, Vol. 101(2), 425–478. doi: 10.1111/j.1365-246X.1990.tb06579.x
https://doi.org/10.1111/j.1365-246X.1990.tb06579.x
11. DeMets C., Gordon R.G., Argus D.F., Stein S. Effect of recent revisions to the geomagnetic reversal time scale on estimates of current plate motions. Geophys. Res. Lett. 1994, Vol. 21(20), 2191–2194. doi: 10.1029/94GL02118
https://doi.org/10.1029/94GL02118
12. DeMets C., Gordon R. G., Argus D. F. Geologically current plate motions. Geophys. J. Int. 2010, Vol. 181(1), 1–80. doi: 10.1111/j.1365-246X.2009.04491.x
https://doi.org/10.1111/j.1365-246X.2009.04491.x
13. Dmitrieva K., Segal P., DeMets C. Network-based estimation of time-dependent noise in GPS position time series. J. Geod. 2015, Vol. 89(6), 591–606. doi: 10.1007/s00190-015-0801-9
https://doi.org/10.1007/s00190-015-0801-9
14. Dong D., Herring T. A., King R. W. Estimating regional deformation from a combination of space and terrestrial geodetic data. J. Geod. 1998, Vol. 72(4), 200–214. doi:10.1007/s001900050161
https://doi.org/10.1007/s001900050161
15. Gazeaux, J., Williams S., King M., Bos M., Dach R., Deo M., Moore A.W., Ostini L., Petrie E., Roggero M., Teferle F. N., Olivares G., Webb F. H. Detecting offsets in GPS time series: first results from the detection of offsets in GPS experiment. J. Geophys. Res. 2013, Vol. 118(B5), 2397–2407. doi:10.1002/jgrb.50152
https://doi.org/10.1002/jgrb.50152
16. Herring, T. MATLAB tools for viewing GPS velocities and time series. GPS Solution. 2003, Vol. 7(3), 194–199. doi:10.1007/s10291-003-0068-0
https://doi.org/10.1007/s10291-003-0068-0
17. Kogan M. G., Steblov G. M. Current global plate kinematics from GPS (1995-2007) with the plate-consistent reference frame. J. Geophys. Res. 2008, Vol. 113(B4), No B04416, 17. doi: 10.1029/2007JB005353
https://doi.org/10.1029/2007JB005353
18. Kremer C., Blewitt G., Klein E.C. A geodetic plate motion and Global Strain Rate Model. Geochemistry, Geophysics, Geosystems. 2014, Vol. 15(10), 3849–3889. doi: 10.1002/2014GC005407
https://doi.org/10.1002/2014GC005407
19. Kremer C., Holt W. E., Haines A. J. An integrated global model of present-day plate motions and plate boundary deformation. Geophys. J. Int. 2003. Vol. 154(1), 8–34. doi:10.1046/j.1365-246X.2003.01917.x
https://doi.org/10.1046/j.1365-246X.2003.01917.x
20. Mao A., Harrison C. G. A., Dixon T. H. Noise in GPS coordinate time series. J. Geophys. Res. 1999, Vol. 104(B2), 2797–2816. doi: 10.1029/1998JB900033
https://doi.org/10.1029/1998JB900033
21. Nikolaidis R. Observation of geodetic and seismic deformation with the Global Positioning System: Ph.D. Thesis. University of California, San Diego, 2002, 265.
22. Sella G. F., Dixon T. H., Mao A. REVEL: A model for recent plate velocities from space geodesy. J. Geophys. Res. 2002. Vol. 107(B4), No 2081, 30. doi: 10.1029/2000JB000033
https://doi.org/10.1029/2000JB000033
23. Silver P. G., Bock Y., Agnew D. C., Henyey T., Linde A. T., McEvilly T. V., Minster J. B., Romanowicz B. A., Sacks I. S., Smith R. B., Solomon S. C., Stein S. A. A plate boundary observatory. Iris Newsletter. 1999. Vol. XVI(2), 3–9.
24. Tadyeyev O., Lutsyk O. Study of the earths surface deformations on the results of GNSS-observations in Europe (2004-2014). Scientific Herald of Uzh. Univ.: Geography. Land management. Nature management. 2014, Is. 3, 27–35.
25. Williams S. D. P. CATS: GPS coordinate time series analysis software. GPS Solution. 2008, Vol. 12(2), 147–153. doi: 10.1007/s10291-007-0086-4
https://doi.org/10.1007/s10291-007-0086-4
26. Williams S. D .P., Bock Y., Fang P., Jamason P., Nikolaidis R. M., Prawirodirdjo L., Miller M., Johnson D. J. Error analysis of continuous GPS position time series. J. Geophys. Res. 2004, Vol. 109(B3), 19. doi: 10.1029/2003JB002741
https://doi.org/10.1029/2003JB002741
27. Wu X., Collilieux X., Altamimi Z., Vermeersen B. L. A., Gross R. S., Fukumori I. Accuracy of the International Terrestrial Reference Frame origin and Earth expansion. Geophys. Res. Lett. 2011, Vol. 38(13), No L13304, 5. doi: 10.1029/2011GL047450
https://doi.org/10.1029/2011GL047450