Recent Relative Vertical Movements in the Tectonic Zone of the Sudety Mts.

Abstract

Recent geodynamic activity of the Sudeten in the area of Poland and the Czech Republic has been confirmed by the results of geodynamic, seismic, geodetic and other tests. This is especially the case for the periodical (the last 25 years) satellite GPS/GNSS and gravimetric measurements in the regional research network GEOSUD, SILESIA, SUDETY and the local geodynamic polygons ("Snieznik", "Stolowe Mts."), as well as observation of crack-gauges on several tectonic faults. Vertical movements are indicated in the maps of recent movements of the Earth’s crust. Two adjacent countries in the area of the Sudeten achieved results from +0.5 mm/year to -2 mm/year with reference to the tide gauge on the coast of the Baltic Sea. They present absolute value received on the basis of a comparison of the results of repeated (in intervals of 20–30 years) measurements of 1st order levelling lines. The characteristics of this data do not allow for an assessment of recent tectonic activity in the Sudety Mts. because the isolines of absolute velocities of vertical movements of the Earth’s crust surface on the maps (Wyrzykowski, 1985; Kowalczyk, 2006; Vyskočil, 2002) present "smoothed" large-area changes without a proof of dynamic changes in the Sudeten tectonic zones. This paper presents results of analysis archival data on repeated measurement precise levelling networks. The results of analysis were used to produce maps of vertical movements of the Earth’s crust surface. Analysis is focused on the part of levelling lines which intersect Sudeten main tectonic faults. This paper included methodology of data processing. In research period relative vertical movements of tectonic zones are referencing to the relative stable benchmark. The values of these velocities between -0.8 ÷ +0.8 mm/year confirm recent geodynamic mobility in this Central European area.Recent geodynamic activity of the Sudeten in the area of Poland and the Czech Republic has been confirmed by the results of geodynamic, seismic, geodetic and other tests. This is especially the case for the periodical (the last 25 years) satellite GPS/GNSS and gravimetric measurements in the regional research network GEOSUD, SILESIA, SUDETY and the local geodynamic polygons ("Snieznik", "Stolowe Mts."), as well as observation of crack-gauges on several tectonic faults. Vertical movements are indicated in the maps of recent movements of the Earth’s crust. Two adjacent countries in the area of the Sudeten achieved results from +0.5 mm/year to -2 mm/year with reference to the tide gauge on the coast of the Baltic Sea. They present absolute value received on the basis of a comparison of the results of repeated (in intervals of 20–30 years) measurements of 1st order levelling lines. The characteristics of this data do not allow for an assessment of recent tectonic activity in the Sudety Mts. because the isolines of absolute velocities of vertical movements of the Earth’s crust surface on the maps (Wyrzykowski, 1985; Kowalczyk, 2006; Vyskočil, 2002) present "smoothed" large-area changes without a proof of dynamic changes in the Sudeten tectonic zones. This paper presents results of analysis archival data on repeated measurement precise levelling networks. The results of analysis were used to produce maps of vertical movements of the Earth’s crust surface. Analysis is focused on the part of levelling lines which intersect Sudeten main tectonic faults. This paper included methodology of data processing. In research period relative vertical movements of tectonic zones are referencing to the relative stable benchmark. The values of these velocities between -0.8 ÷ +0.8 mm/year confirm recent geodynamic mobility in this Central European area.