Determination of the recent rotation poles of the main tectonic plates on the base of GNSS data

The main goal is to determine and analyze the recent rotation poles of the main tectonic plates based on measurements of continuous GNSS stations for the period of 2002–2021. Using procedures based on the method of the least squares, we suggested an algorithm to determine recent rotation poles of tectonic plates on the basis of processing time series of daily solutions of continuous GNSS stations. The algorythm was implemented in the MathCAD software package. It uses, generalizes, and modernizes the approaches presented in previous studies. Structurally, this algorithm consists of five consecutive stages: transformation of data into an internal format; compliance check and time series filtering; determination of horizontal displacement rates; compliance check and filtering of specified velocities; determination of rotation poles. The algorithm involves the use of freely available time series of daily solutions of continuous GNSS stations, or any other data prepared in a similar format. The study has developed an algorithm to determine recent rotation poles of tectonic plates. It is based on processing time series of daily solutions of continuous GNSS stations. The algorithm was tested to define the recent rotation poles of the main tectonic plates. We determined the components of recent horizontal displacement vectors of 3169 continuous GNSS stations located on 7 large, 7 medium and 3 micro plates for the period of 2002-2021 in the ITRF2014/IGS14 reference frame. The accuracy of determining the component vectors of horizontal displacements is in the range of 0.9-6.4 mm and is on average 10–15% of the vector length. The research allowed us to construct a map scheme of the spatial distribution of the velocity field of recent horizontal movements of continuous GNSS stations. Recent rotation poles of the main tectonic plates were determined for the period 2002-2021 in ITRF2014/IGS14 reference frame. It was established that, in general, the obtained values of recent rotation poles correlate well with known models of tectonic plate movements. This confirms the correctness of the chosen method, as well as the reliability of the obtained results. Recent rotation poles of tectonic plates are the basis for modeling and analysis of global, regional and local geodynamic processes, so their accurate determination is an urgent and necessary task. GNSS data is an alternative, and recently, practically irreplaceable basis for determining such parameters. The rapid increase in the number of continuous GNSS stations, as well as the high quality of their measurements, contributes to improving the accuracy of determining the recent rotation poles of tectonic plates, but leads to the need for their constant recalculation and refinement. The presented algorithm and the obtained results can be used to develop new and refine existing models of tectonic plate movements and reference frames, as well as to forecast the movements of the Earth’s crust.