Deformation of the margin of Sudety Mountains (Southern Poland) studied by Persistent Scatterers Interferometry
Zbigniew Perski(1) and Ramon Hanssen(2)
(1) University of Silesia, Bedzinska 60, 41-200 Sosnowiec, Poland
(2) Delft University of Technology, Kluyverweg 1, 2629 HS Delft, Netherlands
The scope of this work was to use the newest achievements in a field of SAR Interferometry to measure recently occurring natural earth surface movements in Poland and near-border areas. Natural recent earth crust surface movement has not yet been fully explored using InSAR. The latest achievements of the multi-images approaches like e.g. Persistent Scatterers Method suggests that such research will be possible to perform. Such data may significantly contribute the verification of geophysical models of occurring deformations. The achievement of such data may have also economical importance: the detailed mapping of the rate and range of deformations may lead to better protection of existing and new industrial and transport constructions.
Persistent Scatterer Interferometry (PSI), pioneered by Polimi researchers early 2000 (Ferretti et al. 2001), is a method for mm-level deformation measurements based of large amount of SAR images. It is an ideal method for non-interventive measurements of stable in time natural radar reflectors like buildings in urbanized areas. The method is very well suitable for slow subsidence monitoring and for a posteriori studies based on archived data. It proved its high potential in urbanized areas (e.g. Las Vegas, Paris, Naples). The latest development of the PS selection procedures shows that PSI techniques might be also successfully applied on rural terrains (e.g. Groningen gas field area), or in natural terrains like volcanoes. The PS-InSAR technique is expanding now towards decorrelated areas with low PS density and a small deformation signal (Ketelaar et al. 2004). Despite the new potential of InSAR, it has never been used to measure slow deformation phenomena related to natural, slow tectonic processes, like the active faults in North-Central Europe.
The current archivement will focus on two areas in southern Poland: Otmuchow area and Wieliczka region.In Otmuchów area two large artificial water reservoirs on Nysa Kłodzka river are located within the tectonic graben of Paczków: Otmuchów Lake and Nysa Lake. The additional loading is caused by water volume increasing natural tectonic stresses in this area (Cacon, Deeb 1995). The geological structure of the area is complex and recently active faults are present: Sudety Marginal Fault and secondary-order faults forming the graben. Recent GPS geodynamical measurements within international project GEOSUD II have reported the highest rates of deformations (some mm/year) in Paczkow Graben. Application of PSInSAR technology within this area confirmed the high dynamics of the recent tectonical activity of Paczkow Graben. For data processing, we used the Integer Least Squares (ILSQ) PSI concept developed at TU Delft. The localized relative subsidence and uplift phenomena of some mm/year were found. Their locations correspond well with tectonic structure of the area.
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,