J. Rogowski

Activities of the Astro-geodetic Observatory in Jozefoslaw in the frame of IGS and EUREF

Abstract The Astrogeodetic Observatory of the Institute of Geodesy and Geodetic Astronomy of the Warsaw University of Technology (WUT) in Jozefoslaw was incorporated in 1957. In 1991 it joined the International GPS Service (IGS) and started to operate as a permanent in 1993. Since then the following permanent services have been maintained: GPS observations using Trimble and Turbo Rogue receivers, tidal gravimetric observations with LaCoste&Romberg model D gravimeter and meteorological observations. Since 1995 WUT Local Analysis Centre, one of the 11 Local Analysis Centres acting in Europe, has started the systematic day-to-day processing of a selected number of European sites in the frame of the EUREF network. It also processes national and international GPS campaigns (CEGRN, EXTENDED SAGET etc.), models ionosphere and troposphere, computes tidal components and changes of the vertical according to astrometrical and gravimetric measurements. For the last 4 years the Centre has processed and analysed a lot of scientific enterprises carried out within the confines of the Central European Initiative (CEI). This paper presents the current state of the art of the Observatorys activities. It deals with the acting of it and participating of the WUT Local Analysis Centre in the international scientific projects.

Common Experiment of the Analysis Centre CODE and the Institute of Geodesy and Geodetic Astronomy of Warsaw University of Technology (IGGA WUT) on the Combination of Regional and Global Solutions

Since January 1995 the CODE Processing Centre and the Institute of Geodesy and Geodetic Astronomy of Warsaw University of Technology entered into cooperation aimed at testing different processing methods for the Polish network consisting of 3 permanent IGS stations: Jozefoslaw, Borowiec and Lamkowko. The connection to the global reference frame is realised by processing 4 additional European IGS stations: Wettzell, Kootwijk, Metsahovi and Onsala. The results of four different processing strategies are compared with the results achieved by CODE from the global network. The experiment is a practical test of the idea of IGS regional data processing expected for IGS Associated Analysis Centre Type I. Particular attention is paid to the impact of the orbits (CODE vs.IGS) and the influence of the troposphere parameter estimation on the station coordinates. Since end of March 1995 the second receiver a TURBO ROGUE SNR 8000, was included into the permanent network. The results of data processing using the same computation strategies as well as results of the combination with the global solution are shown. The preliminary results of this work are shortly reported in the paper. The experiment of combining global CODE solutions with regional solutions was also tested with the EXTENDED SAGET’94 Network.

Variation of Point Positions and Gravity Field in the Area of Intensive Mining

The results of periodic satellite GPS and gravimetric measurements accomplished in the area of intensive mining near Wodzislaw Slash (Upper Silesia Region) are reported in the paper. Procedures of establishing GPS control networks in this kind of areas are discussed. Changes of gravity Bouguer anomalies and displacements of surface points are shown as a complement of the mining exploitation data.

Geodynamic Studies in the Polish Part of the Teisseyre-Tornquist Zone

Geologic structure of Central Europe is characterized by three main types of geotectonic units . They are: Paleozoic folds in western and south-western part of Europe (West European Paleozoic Platform), the oldest geologic unit — East European Precambrian Platform and the Alpine Orogeny in the southern part of Europe. It is easy to recognize that all these three geotectonic units just meet on the territory of Poland forming in southeastern part of Poland so called “tectonic knot”. The general scheme of tectonic units occurring on the territory of Poland based on results of deep seismic soundings can be seen in Fig. 1. The arrows show directions in which Moho discontinuity increases. It can be also seen that Poland is cut by Teisseyre-Tornquist’s zone, i.e. by the border between Paleozoic Platform and Precambrian Platform.

GPS for large-scale aerotriangulation

The application of GPS (Global Positioning System) measurements to photogrammetry is presented. The technology of establishment of a GPS network for aerotriangulation as a base for mapping at scales from 1:1000 has been worked out at the Institute of Geodesy and Geodetical Astronomy of the Warsaw University of Technology. This method consists of the design, measurement, and adjustment of this special network. The results of several pilot projects confirm the possibility of improving the aerotriangulation accuracy. A few-centimeter accuracy has been achieved.<<ETX>>